From 7fcbed159ad29e6479afa5fffda0863fd6dd3635 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Mon, 16 Mar 2026 13:20:23 +0000
Subject: [PATCH 01/29] wip

---
 packages/cash-account-service/CHANGELOG.md    |  14 ++
 packages/cash-account-service/LICENSE         |  21 +++
 packages/cash-account-service/README.md       |  17 +++
 packages/cash-account-service/jest.config.js  |  26 ++++
 packages/cash-account-service/package.json    |  74 +++++++++
 .../CashAccountService-method-action-types.ts |   9 ++
 .../src/CashAccountService.test.ts            | 144 ++++++++++++++++++
 .../src/CashAccountService.ts                 |  66 ++++++++
 packages/cash-account-service/src/index.ts    |   9 ++
 packages/cash-account-service/src/types.ts    |  24 +++
 .../cash-account-service/tsconfig.build.json  |  14 ++
 packages/cash-account-service/tsconfig.json   |  12 ++
 packages/cash-account-service/typedoc.json    |   7 +
 packages/keyring-controller/package.json      |   1 +
 .../src/KeyringController.ts                  |   3 +
 tsconfig.build.json                           |   3 +
 yarn.lock                                     |  66 ++++++++
 17 files changed, 510 insertions(+)
 create mode 100644 packages/cash-account-service/CHANGELOG.md
 create mode 100644 packages/cash-account-service/LICENSE
 create mode 100644 packages/cash-account-service/README.md
 create mode 100644 packages/cash-account-service/jest.config.js
 create mode 100644 packages/cash-account-service/package.json
 create mode 100644 packages/cash-account-service/src/CashAccountService-method-action-types.ts
 create mode 100644 packages/cash-account-service/src/CashAccountService.test.ts
 create mode 100644 packages/cash-account-service/src/CashAccountService.ts
 create mode 100644 packages/cash-account-service/src/index.ts
 create mode 100644 packages/cash-account-service/src/types.ts
 create mode 100644 packages/cash-account-service/tsconfig.build.json
 create mode 100644 packages/cash-account-service/tsconfig.json
 create mode 100644 packages/cash-account-service/typedoc.json

diff --git a/packages/cash-account-service/CHANGELOG.md b/packages/cash-account-service/CHANGELOG.md
new file mode 100644
index 00000000000..8fcf72c699c
--- /dev/null
+++ b/packages/cash-account-service/CHANGELOG.md
@@ -0,0 +1,14 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- Initial release
+
+[Unreleased]: https://github.com/MetaMask/core/
diff --git a/packages/cash-account-service/LICENSE b/packages/cash-account-service/LICENSE
new file mode 100644
index 00000000000..c259cd7ebcf
--- /dev/null
+++ b/packages/cash-account-service/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025 MetaMask
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/packages/cash-account-service/README.md b/packages/cash-account-service/README.md
new file mode 100644
index 00000000000..66994ad4cd6
--- /dev/null
+++ b/packages/cash-account-service/README.md
@@ -0,0 +1,17 @@
+# `@metamask/cash-account-service`
+
+Cash account service.
+
+This service provides operations for creating and managing Cash accounts derived from HD keyrings.
+
+## Installation
+
+`yarn add @metamask/cash-account-service`
+
+or
+
+`npm install @metamask/cash-account-service`
+
+## Contributing
+
+This package is part of a monorepo. Instructions for contributing can be found in the [monorepo README](https://github.com/MetaMask/core#readme).
diff --git a/packages/cash-account-service/jest.config.js b/packages/cash-account-service/jest.config.js
new file mode 100644
index 00000000000..ca084133399
--- /dev/null
+++ b/packages/cash-account-service/jest.config.js
@@ -0,0 +1,26 @@
+/*
+ * For a detailed explanation regarding each configuration property and type check, visit:
+ * https://jestjs.io/docs/configuration
+ */
+
+const merge = require('deepmerge');
+const path = require('path');
+
+const baseConfig = require('../../jest.config.packages');
+
+const displayName = path.basename(__dirname);
+
+module.exports = merge(baseConfig, {
+  // The display name when running multiple projects
+  displayName,
+
+  // An object that configures minimum threshold enforcement for coverage results
+  coverageThreshold: {
+    global: {
+      branches: 100,
+      functions: 100,
+      lines: 100,
+      statements: 100,
+    },
+  },
+});
diff --git a/packages/cash-account-service/package.json b/packages/cash-account-service/package.json
new file mode 100644
index 00000000000..5d924c899cc
--- /dev/null
+++ b/packages/cash-account-service/package.json
@@ -0,0 +1,74 @@
+{
+  "name": "@metamask/cash-account-service",
+  "version": "0.0.0",
+  "description": "Service to manage cash accounts",
+  "keywords": [
+    "MetaMask",
+    "Ethereum"
+  ],
+  "homepage": "https://github.com/MetaMask/core/tree/main/packages/cash-account-service#readme",
+  "bugs": {
+    "url": "https://github.com/MetaMask/core/issues"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/MetaMask/core.git"
+  },
+  "license": "MIT",
+  "sideEffects": false,
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./dist/index.d.mts",
+        "default": "./dist/index.mjs"
+      },
+      "require": {
+        "types": "./dist/index.d.cts",
+        "default": "./dist/index.cjs"
+      }
+    },
+    "./package.json": "./package.json"
+  },
+  "main": "./dist/index.cjs",
+  "types": "./dist/index.d.cts",
+  "files": [
+    "dist/"
+  ],
+  "scripts": {
+    "build": "ts-bridge --project tsconfig.build.json --verbose --clean --no-references",
+    "build:all": "ts-bridge --project tsconfig.build.json --verbose --clean",
+    "build:docs": "typedoc",
+    "changelog:update": "../../scripts/update-changelog.sh @metamask/cash-account-service",
+    "changelog:validate": "../../scripts/validate-changelog.sh @metamask/cash-account-service",
+    "since-latest-release": "../../scripts/since-latest-release.sh",
+    "test": "NODE_OPTIONS=--experimental-vm-modules jest --reporters=jest-silent-reporter",
+    "test:clean": "NODE_OPTIONS=--experimental-vm-modules jest --clearCache",
+    "test:verbose": "NODE_OPTIONS=--experimental-vm-modules jest --verbose",
+    "test:watch": "NODE_OPTIONS=--experimental-vm-modules jest --watch"
+  },
+  "dependencies": {
+    "@metamask/base-controller": "^9.0.0",
+    "@metamask/keyring-controller": "^25.1.0",
+    "@metamask/messenger": "^0.3.0",
+    "@metamask/utils": "^11.9.0"
+  },
+  "devDependencies": {
+    "@metamask/auto-changelog": "^3.4.4",
+    "@metamask/eth-hd-keyring": "^13.0.0",
+    "@ts-bridge/cli": "^0.6.4",
+    "@types/jest": "^29.5.14",
+    "deepmerge": "^4.2.2",
+    "jest": "^29.7.0",
+    "ts-jest": "^29.2.5",
+    "typedoc": "^0.25.13",
+    "typedoc-plugin-missing-exports": "^2.0.0",
+    "typescript": "~5.3.3"
+  },
+  "engines": {
+    "node": "^18.18 || >=20"
+  },
+  "publishConfig": {
+    "access": "public",
+    "registry": "https://registry.npmjs.org/"
+  }
+}
diff --git a/packages/cash-account-service/src/CashAccountService-method-action-types.ts b/packages/cash-account-service/src/CashAccountService-method-action-types.ts
new file mode 100644
index 00000000000..cec0dacad8b
--- /dev/null
+++ b/packages/cash-account-service/src/CashAccountService-method-action-types.ts
@@ -0,0 +1,9 @@
+import type { CashAccountService } from './CashAccountService';
+
+export type CashAccountServiceCreateCashAccountAction = {
+  type: `CashAccountService:createCashAccount`;
+  handler: CashAccountService['createCashAccount'];
+};
+
+export type CashAccountServiceMethodActions =
+  CashAccountServiceCreateCashAccountAction;
diff --git a/packages/cash-account-service/src/CashAccountService.test.ts b/packages/cash-account-service/src/CashAccountService.test.ts
new file mode 100644
index 00000000000..d0de4f9cd64
--- /dev/null
+++ b/packages/cash-account-service/src/CashAccountService.test.ts
@@ -0,0 +1,144 @@
+import type { HdKeyring } from '@metamask/eth-hd-keyring';
+import { KeyringTypes } from '@metamask/keyring-controller';
+import type { KeyringObject } from '@metamask/keyring-controller';
+import type {
+  MessengerActions,
+  MessengerEvents,
+  MockAnyNamespace,
+} from '@metamask/messenger';
+import { Messenger, MOCK_ANY_NAMESPACE } from '@metamask/messenger';
+
+import { CashAccountService, serviceName } from './CashAccountService';
+import type { CashAccountServiceMessenger } from './types';
+
+type AllActions = MessengerActions<CashAccountServiceMessenger>;
+type AllEvents = MessengerEvents<CashAccountServiceMessenger>;
+
+type RootMessenger = Messenger<MockAnyNamespace, AllActions, AllEvents>;
+
+const MOCK_MNEMONIC = new Uint8Array([
+  116, 101, 115, 116, 32, 116, 101, 115, 116, 32, 116, 101, 115, 116, 32, 116,
+  101, 115, 116, 32, 116, 101, 115, 116, 32, 116, 101, 115, 116, 32, 116, 101,
+  115, 116, 32, 116, 101, 115, 116, 32, 116, 101, 115, 116, 32, 116, 101, 115,
+  116, 32, 116, 101, 115, 116, 32, 106, 117, 110, 107,
+]);
+
+const MOCK_ENTROPY_SOURCE = 'mock-entropy-source-id';
+
+const MOCK_HD_KEYRING: KeyringObject = {
+  type: KeyringTypes.hd,
+  accounts: ['0x1234'],
+  metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+};
+
+function setup(): {
+  service: CashAccountService;
+  rootMessenger: RootMessenger;
+  mocks: {
+    getState: jest.Mock;
+    getKeyringsByType: jest.Mock;
+    addNewKeyring: jest.Mock;
+  };
+} {
+  const rootMessenger: RootMessenger = new Messenger({
+    namespace: MOCK_ANY_NAMESPACE,
+    captureException: jest.fn(),
+  });
+
+  const messenger: CashAccountServiceMessenger = new Messenger({
+    namespace: serviceName,
+    parent: rootMessenger,
+  });
+
+  rootMessenger.delegate({
+    messenger,
+    actions: [
+      'KeyringController:getState',
+      'KeyringController:getKeyringsByType',
+      'KeyringController:addNewKeyring',
+    ],
+    events: [],
+  });
+
+  const mocks = {
+    getState: jest.fn().mockReturnValue({
+      isUnlocked: true,
+      keyrings: [MOCK_HD_KEYRING],
+    }),
+    getKeyringsByType: jest
+      .fn()
+      .mockReturnValue([{ mnemonic: MOCK_MNEMONIC } as unknown as HdKeyring]),
+    addNewKeyring: jest.fn().mockResolvedValue({
+      id: 'new-cash-keyring-id',
+      name: '',
+    }),
+  };
+
+  rootMessenger.registerActionHandler(
+    'KeyringController:getState',
+    mocks.getState,
+  );
+  rootMessenger.registerActionHandler(
+    'KeyringController:getKeyringsByType',
+    mocks.getKeyringsByType,
+  );
+  rootMessenger.registerActionHandler(
+    'KeyringController:addNewKeyring',
+    mocks.addNewKeyring,
+  );
+
+  const service = new CashAccountService({ messenger });
+
+  return { service, rootMessenger, mocks };
+}
+
+describe('CashAccountService', () => {
+  describe('createCashAccount', () => {
+    it('creates a Cash keyring from the HD keyring mnemonic', async () => {
+      const { service, mocks } = setup();
+
+      const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
+
+      expect(mocks.getKeyringsByType).toHaveBeenCalledWith(KeyringTypes.hd);
+      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.cash, {
+        mnemonic: MOCK_MNEMONIC,
+      });
+      expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
+    });
+
+    it('is callable via the messenger', async () => {
+      const { rootMessenger } = setup();
+
+      const result = await rootMessenger.call(
+        'CashAccountService:createCashAccount',
+        MOCK_ENTROPY_SOURCE,
+      );
+
+      expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
+    });
+
+    it('throws if no HD keyring matches the entropy source', async () => {
+      const { service } = setup();
+
+      await expect(
+        service.createCashAccount('nonexistent-entropy-source'),
+      ).rejects.toThrow(
+        'No HD keyring found for entropy source: nonexistent-entropy-source',
+      );
+    });
+
+    it('throws if the HD keyring has no mnemonic', async () => {
+      const { service, mocks } = setup();
+
+      mocks.getKeyringsByType.mockReturnValue([
+        { mnemonic: null } as unknown as HdKeyring,
+      ]);
+
+      await expect(
+        service.createCashAccount(MOCK_ENTROPY_SOURCE),
+      ).rejects.toThrow(
+        'HD keyring does not have a mnemonic for the given entropy source.',
+      );
+    });
+  });
+});
diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/cash-account-service/src/CashAccountService.ts
new file mode 100644
index 00000000000..a1a1d312111
--- /dev/null
+++ b/packages/cash-account-service/src/CashAccountService.ts
@@ -0,0 +1,66 @@
+import type { HdKeyring } from '@metamask/eth-hd-keyring';
+import { KeyringTypes } from '@metamask/keyring-controller';
+import type {
+  KeyringMetadata,
+  KeyringObject,
+} from '@metamask/keyring-controller';
+
+import type { CashAccountServiceMessenger } from './types';
+
+export const serviceName = 'CashAccountService';
+
+const MESSENGER_EXPOSED_METHODS = ['createCashAccount'] as const;
+
+export class CashAccountService {
+  readonly #messenger: CashAccountServiceMessenger;
+
+  name: typeof serviceName = serviceName;
+
+  constructor({ messenger }: { messenger: CashAccountServiceMessenger }) {
+    this.#messenger = messenger;
+
+    this.#messenger.registerMethodActionHandlers(
+      this,
+      MESSENGER_EXPOSED_METHODS,
+    );
+  }
+
+  /**
+   * Creates a Cash keyring derived from the HD keyring identified by
+   * the given entropy source, and returns the new keyring's metadata.
+   *
+   * @param entropySource - The metadata id of the HD keyring to derive from.
+   * @returns The metadata of the newly created Cash keyring.
+   */
+  async createCashAccount(entropySource: string): Promise<KeyringMetadata> {
+    const { keyrings } = this.#messenger.call('KeyringController:getState');
+
+    const hdKeyringIndex = keyrings.findIndex(
+      (kr: KeyringObject) =>
+        kr.type === KeyringTypes.hd && kr.metadata.id === entropySource,
+    );
+    if (hdKeyringIndex === -1) {
+      throw new Error(
+        `No HD keyring found for entropy source: ${entropySource}`,
+      );
+    }
+
+    const hdKeyrings = this.#messenger.call(
+      'KeyringController:getKeyringsByType',
+      KeyringTypes.hd,
+    ) as HdKeyring[];
+
+    const hdKeyring = hdKeyrings[hdKeyringIndex];
+    if (!hdKeyring?.mnemonic) {
+      throw new Error(
+        'HD keyring does not have a mnemonic for the given entropy source.',
+      );
+    }
+
+    return await this.#messenger.call(
+      'KeyringController:addNewKeyring',
+      KeyringTypes.cash,
+      { mnemonic: hdKeyring.mnemonic },
+    );
+  }
+}
diff --git a/packages/cash-account-service/src/index.ts b/packages/cash-account-service/src/index.ts
new file mode 100644
index 00000000000..46d1826ad6e
--- /dev/null
+++ b/packages/cash-account-service/src/index.ts
@@ -0,0 +1,9 @@
+export type {
+  CashAccountServiceActions,
+  CashAccountServiceMessenger,
+} from './types';
+export type {
+  CashAccountServiceCreateCashAccountAction,
+  CashAccountServiceMethodActions,
+} from './CashAccountService-method-action-types';
+export { CashAccountService } from './CashAccountService';
diff --git a/packages/cash-account-service/src/types.ts b/packages/cash-account-service/src/types.ts
new file mode 100644
index 00000000000..cc1a3ded936
--- /dev/null
+++ b/packages/cash-account-service/src/types.ts
@@ -0,0 +1,24 @@
+import type {
+  KeyringControllerAddNewKeyringAction,
+  KeyringControllerGetKeyringsByTypeAction,
+  KeyringControllerGetStateAction,
+} from '@metamask/keyring-controller';
+import type { Messenger } from '@metamask/messenger';
+
+import type { serviceName } from './CashAccountService';
+import type { CashAccountServiceMethodActions } from './CashAccountService-method-action-types';
+
+export type CashAccountServiceActions = CashAccountServiceMethodActions;
+
+type AllowedActions =
+  | KeyringControllerGetStateAction
+  | KeyringControllerGetKeyringsByTypeAction
+  | KeyringControllerAddNewKeyringAction;
+
+type AllowedEvents = never;
+
+export type CashAccountServiceMessenger = Messenger<
+  typeof serviceName,
+  CashAccountServiceActions | AllowedActions,
+  AllowedEvents
+>;
diff --git a/packages/cash-account-service/tsconfig.build.json b/packages/cash-account-service/tsconfig.build.json
new file mode 100644
index 00000000000..b16ce7cfcda
--- /dev/null
+++ b/packages/cash-account-service/tsconfig.build.json
@@ -0,0 +1,14 @@
+{
+  "extends": "../../tsconfig.packages.build.json",
+  "compilerOptions": {
+    "baseUrl": "./",
+    "outDir": "./dist",
+    "rootDir": "./src"
+  },
+  "references": [
+    { "path": "../base-controller/tsconfig.build.json" },
+    { "path": "../keyring-controller/tsconfig.build.json" },
+    { "path": "../messenger/tsconfig.build.json" }
+  ],
+  "include": ["../../types", "./src"]
+}
diff --git a/packages/cash-account-service/tsconfig.json b/packages/cash-account-service/tsconfig.json
new file mode 100644
index 00000000000..775a9ba69b6
--- /dev/null
+++ b/packages/cash-account-service/tsconfig.json
@@ -0,0 +1,12 @@
+{
+  "extends": "../../tsconfig.packages.json",
+  "compilerOptions": {
+    "baseUrl": "./"
+  },
+  "references": [
+    { "path": "../base-controller" },
+    { "path": "../keyring-controller" },
+    { "path": "../messenger" }
+  ],
+  "include": ["../../types", "./src"]
+}
diff --git a/packages/cash-account-service/typedoc.json b/packages/cash-account-service/typedoc.json
new file mode 100644
index 00000000000..c9da015dbf8
--- /dev/null
+++ b/packages/cash-account-service/typedoc.json
@@ -0,0 +1,7 @@
+{
+  "entryPoints": ["./src/index.ts"],
+  "excludePrivate": true,
+  "hideGenerator": true,
+  "out": "docs",
+  "tsconfig": "./tsconfig.build.json"
+}
diff --git a/packages/keyring-controller/package.json b/packages/keyring-controller/package.json
index 413009e83a7..d470ee909e1 100644
--- a/packages/keyring-controller/package.json
+++ b/packages/keyring-controller/package.json
@@ -48,6 +48,7 @@
   },
   "dependencies": {
     "@ethereumjs/util": "^9.1.0",
+    "@metamask-previews/eth-cash-keyring": "0.0.0-25e4b24",
     "@metamask/base-controller": "^9.0.0",
     "@metamask/browser-passworder": "^6.0.0",
     "@metamask/eth-hd-keyring": "^13.0.0",
diff --git a/packages/keyring-controller/src/KeyringController.ts b/packages/keyring-controller/src/KeyringController.ts
index add11e8183b..788ec8a88b5 100644
--- a/packages/keyring-controller/src/KeyringController.ts
+++ b/packages/keyring-controller/src/KeyringController.ts
@@ -28,6 +28,7 @@ import {
   isValidJson,
   remove0x,
 } from '@metamask/utils';
+import { CashKeyring } from '@metamask-previews/eth-cash-keyring';
 import { Mutex } from 'async-mutex';
 import type { MutexInterface } from 'async-mutex';
 import Wallet, { thirdparty as importers } from 'ethereumjs-wallet';
@@ -55,6 +56,7 @@ export enum KeyringTypes {
   /* eslint-disable @typescript-eslint/naming-convention */
   simple = 'Simple Key Pair',
   hd = 'HD Key Tree',
+  cash = 'Cash Keyring',
   qr = 'QR Hardware Wallet Device',
   trezor = 'Trezor Hardware',
   oneKey = 'OneKey Hardware',
@@ -558,6 +560,7 @@ const defaultKeyringBuilders = [
   // @ts-expect-error keyring types are mismatched
   keyringBuilderFactory(SimpleKeyring),
   keyringBuilderFactory(HdKeyring),
+  keyringBuilderFactory(CashKeyring),
 ];
 
 export const getDefaultKeyringState = (): KeyringControllerState => {
diff --git a/tsconfig.build.json b/tsconfig.build.json
index 0b4716238fb..546267cfba1 100644
--- a/tsconfig.build.json
+++ b/tsconfig.build.json
@@ -55,6 +55,9 @@
     {
       "path": "./packages/build-utils/tsconfig.build.json"
     },
+    {
+      "path": "./packages/cash-account-service/tsconfig.build.json"
+    },
     {
       "path": "./packages/chain-agnostic-permission/tsconfig.build.json"
     },
diff --git a/yarn.lock b/yarn.lock
index 529185d3373..ec1ff5d708f 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2485,6 +2485,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@metamask-previews/eth-cash-keyring@npm:0.0.0-25e4b24":
+  version: 0.0.0-25e4b24
+  resolution: "@metamask-previews/eth-cash-keyring@npm:0.0.0-25e4b24"
+  dependencies:
+    "@metamask/eth-hd-keyring": "npm:13.1.0"
+  checksum: 10/468cd1afb1a498406cd2b4dd01f5059fc7313739b30c9ed066789f779dc784b7dc5baee982565da334671700a4f0a0bf2c45818040b7b656452700ff36b1a07b
+  languageName: node
+  linkType: hard
+
 "@metamask/7715-permission-types@npm:^0.5.0":
   version: 0.5.0
   resolution: "@metamask/7715-permission-types@npm:0.5.0"
@@ -3104,6 +3113,27 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@metamask/cash-account-service@workspace:packages/cash-account-service":
+  version: 0.0.0-use.local
+  resolution: "@metamask/cash-account-service@workspace:packages/cash-account-service"
+  dependencies:
+    "@metamask/auto-changelog": "npm:^3.4.4"
+    "@metamask/base-controller": "npm:^9.0.0"
+    "@metamask/eth-hd-keyring": "npm:^13.0.0"
+    "@metamask/keyring-controller": "npm:^25.1.0"
+    "@metamask/messenger": "npm:^0.3.0"
+    "@metamask/utils": "npm:^11.9.0"
+    "@ts-bridge/cli": "npm:^0.6.4"
+    "@types/jest": "npm:^29.5.14"
+    deepmerge: "npm:^4.2.2"
+    jest: "npm:^29.7.0"
+    ts-jest: "npm:^29.2.5"
+    typedoc: "npm:^0.25.13"
+    typedoc-plugin-missing-exports: "npm:^2.0.0"
+    typescript: "npm:~5.3.3"
+  languageName: unknown
+  linkType: soft
+
 "@metamask/chain-agnostic-permission@npm:^1.4.0, @metamask/chain-agnostic-permission@workspace:packages/chain-agnostic-permission":
   version: 0.0.0-use.local
   resolution: "@metamask/chain-agnostic-permission@workspace:packages/chain-agnostic-permission"
@@ -3673,6 +3703,24 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@metamask/eth-hd-keyring@npm:13.1.0":
+  version: 13.1.0
+  resolution: "@metamask/eth-hd-keyring@npm:13.1.0"
+  dependencies:
+    "@ethereumjs/tx": "npm:^5.4.0"
+    "@ethereumjs/util": "npm:^9.1.0"
+    "@metamask/eth-sig-util": "npm:^8.2.0"
+    "@metamask/key-tree": "npm:^10.0.2"
+    "@metamask/keyring-api": "npm:^21.3.0"
+    "@metamask/keyring-utils": "npm:^3.1.0"
+    "@metamask/scure-bip39": "npm:^2.1.1"
+    "@metamask/superstruct": "npm:^3.1.0"
+    "@metamask/utils": "npm:^11.1.0"
+    ethereum-cryptography: "npm:^2.1.2"
+  checksum: 10/7d67c29c6387ffe871995e67e4802b9a6f6eb2f14b556e43690509b342ef66b72765477b27e4b669fe8a00606e219e00991f94da3a74fcedcf339ab765215ae6
+  languageName: node
+  linkType: hard
+
 "@metamask/eth-hd-keyring@npm:^13.0.0":
   version: 13.0.0
   resolution: "@metamask/eth-hd-keyring@npm:13.0.0"
@@ -4157,6 +4205,23 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@metamask/keyring-api@npm:^21.3.0":
+  version: 21.5.0
+  resolution: "@metamask/keyring-api@npm:21.5.0"
+  dependencies:
+    "@ethereumjs/tx": "npm:^5.4.0"
+    "@metamask/eth-sig-util": "npm:^8.2.0"
+    "@metamask/keyring-utils": "npm:^3.2.0"
+    "@metamask/superstruct": "npm:^3.1.0"
+    "@metamask/utils": "npm:^11.1.0"
+    "@types/uuid": "npm:^9.0.8"
+    async-mutex: "npm:^0.5.0"
+    bitcoin-address-validation: "npm:^2.2.3"
+    uuid: "npm:^9.0.1"
+  checksum: 10/a7f2a8c66bc76edabde15b66b80904208b71fd62406ebb91579db4c65d74a8f66db6c610afe265823313df7423b6727a4de03cb1f43e41d840d51a5039f9ef4d
+  languageName: node
+  linkType: hard
+
 "@metamask/keyring-api@npm:^21.4.0, @metamask/keyring-api@npm:^21.6.0":
   version: 21.6.0
   resolution: "@metamask/keyring-api@npm:21.6.0"
@@ -4183,6 +4248,7 @@ __metadata:
     "@ethereumjs/util": "npm:^9.1.0"
     "@lavamoat/allow-scripts": "npm:^3.0.4"
     "@lavamoat/preinstall-always-fail": "npm:^2.1.0"
+    "@metamask-previews/eth-cash-keyring": "npm:0.0.0-25e4b24"
     "@metamask/auto-changelog": "npm:^3.4.4"
     "@metamask/base-controller": "npm:^9.0.0"
     "@metamask/browser-passworder": "npm:^6.0.0"

From b960c58608d30d358b93aaa25aeda6b6dbb4af00 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Mon, 16 Mar 2026 15:44:55 +0000
Subject: [PATCH 02/29] fix: add codeowner

---
 .github/CODEOWNERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index 331f1487491..db34828ff76 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -38,6 +38,7 @@
 
 ## Earn Team
 /packages/earn-controller                   @MetaMask/metamask-earn
+/packages/cash-account-service               @MetaMask/metamask-earn
 
 ## Social AI Team
 /packages/ai-controllers                    @MetaMask/social-ai

From 890ecc1280ff045f9048053583d55c7f4ab785ac Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Tue, 17 Mar 2026 12:04:48 +0000
Subject: [PATCH 03/29] chore: add missing code owner rules

---
 .github/CODEOWNERS | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index db34828ff76..3e10a5b7016 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -38,7 +38,7 @@
 
 ## Earn Team
 /packages/earn-controller                   @MetaMask/metamask-earn
-/packages/cash-account-service               @MetaMask/metamask-earn
+/packages/cash-account-service              @MetaMask/metamask-earn
 
 ## Social AI Team
 /packages/ai-controllers                    @MetaMask/social-ai
@@ -137,6 +137,9 @@
 /packages/assets-controllers/CHANGELOG.md         @MetaMask/metamask-assets @MetaMask/core-platform
 /packages/assets-controller/package.json          @MetaMask/metamask-assets @MetaMask/core-platform
 /packages/assets-controller/CHANGELOG.md          @MetaMask/metamask-assets @MetaMask/core-platform
+
+/packages/cash-account-service/package.json       @MetaMask/metamask-earn @MetaMask/core-platform
+/packages/cash-account-service/CHANGELOG.md       @MetaMask/metamask-earn @MetaMask/core-platform
 /packages/chain-agnostic-permission/package.json  @MetaMask/wallet-integrations @MetaMask/core-platform
 /packages/chain-agnostic-permission/CHANGELOG.md  @MetaMask/wallet-integrations @MetaMask/core-platform
 /packages/config-registry-controller/CHANGELOG.md @MetaMask/networks @MetaMask/core-platform

From 69183918077a0f1fdb9a0b54b9fea6c732f31ba1 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Tue, 17 Mar 2026 12:13:10 +0000
Subject: [PATCH 04/29] chore: dedupe deps

---
 yarn.lock | 17 +----------------
 1 file changed, 1 insertion(+), 16 deletions(-)

diff --git a/yarn.lock b/yarn.lock
index ec1ff5d708f..b6a6e7a59a9 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3703,7 +3703,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@metamask/eth-hd-keyring@npm:13.1.0":
+"@metamask/eth-hd-keyring@npm:13.1.0, @metamask/eth-hd-keyring@npm:^13.0.0":
   version: 13.1.0
   resolution: "@metamask/eth-hd-keyring@npm:13.1.0"
   dependencies:
@@ -3721,21 +3721,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@metamask/eth-hd-keyring@npm:^13.0.0":
-  version: 13.0.0
-  resolution: "@metamask/eth-hd-keyring@npm:13.0.0"
-  dependencies:
-    "@ethereumjs/util": "npm:^9.1.0"
-    "@metamask/eth-sig-util": "npm:^8.2.0"
-    "@metamask/key-tree": "npm:^10.0.2"
-    "@metamask/keyring-utils": "npm:^3.1.0"
-    "@metamask/scure-bip39": "npm:^2.1.1"
-    "@metamask/utils": "npm:^11.1.0"
-    ethereum-cryptography: "npm:^2.1.2"
-  checksum: 10/fe955a4e0331090df8110dbd8f46ea6286c2ad20e6677ecf535361ea9d0008194b2043eddd692cd7ceac2e033a54e4e340caa7d302bd5211826cb252b526f6bc
-  languageName: node
-  linkType: hard
-
 "@metamask/eth-json-rpc-filters@npm:^9.0.0":
   version: 9.0.0
   resolution: "@metamask/eth-json-rpc-filters@npm:9.0.0"

From 8f6c75d5c30899086fb8567d516c76609b2933d7 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Tue, 17 Mar 2026 13:19:31 +0000
Subject: [PATCH 05/29] fix: handle non-hd keyrings in index check

---
 .../src/CashAccountService.test.ts            | 23 +++++++++++++++++++
 .../src/CashAccountService.ts                 |  8 ++++---
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/packages/cash-account-service/src/CashAccountService.test.ts b/packages/cash-account-service/src/CashAccountService.test.ts
index d0de4f9cd64..041eb846507 100644
--- a/packages/cash-account-service/src/CashAccountService.test.ts
+++ b/packages/cash-account-service/src/CashAccountService.test.ts
@@ -117,6 +117,29 @@ describe('CashAccountService', () => {
       expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
     });
 
+    it('finds the correct HD keyring when non-HD keyrings precede it', async () => {
+      const { service, mocks } = setup();
+      mocks.getState.mockReturnValue({
+        isUnlocked: true,
+        keyrings: [
+          {
+            type: KeyringTypes.simple,
+            accounts: ['0xabc'],
+            metadata: { id: 'simple-1', name: '' },
+          },
+          MOCK_HD_KEYRING,
+        ],
+      });
+
+      const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
+
+      expect(mocks.getKeyringsByType).toHaveBeenCalledWith(KeyringTypes.hd);
+      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.cash, {
+        mnemonic: MOCK_MNEMONIC,
+      });
+      expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
+    });
+
     it('throws if no HD keyring matches the entropy source', async () => {
       const { service } = setup();
 
diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/cash-account-service/src/CashAccountService.ts
index a1a1d312111..f3dd1cd57c3 100644
--- a/packages/cash-account-service/src/CashAccountService.ts
+++ b/packages/cash-account-service/src/CashAccountService.ts
@@ -35,9 +35,11 @@ export class CashAccountService {
   async createCashAccount(entropySource: string): Promise<KeyringMetadata> {
     const { keyrings } = this.#messenger.call('KeyringController:getState');
 
-    const hdKeyringIndex = keyrings.findIndex(
-      (kr: KeyringObject) =>
-        kr.type === KeyringTypes.hd && kr.metadata.id === entropySource,
+    const hdKeyringsFromState = keyrings.filter(
+      (kr: KeyringObject) => kr.type === KeyringTypes.hd,
+    );
+    const hdKeyringIndex = hdKeyringsFromState.findIndex(
+      (kr: KeyringObject) => kr.metadata.id === entropySource,
     );
     if (hdKeyringIndex === -1) {
       throw new Error(

From 882cff2c36b6dc487de146a0b5db503acae1563d Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Tue, 17 Mar 2026 13:27:47 +0000
Subject: [PATCH 06/29] chore: use withKeyRing

---
 .../src/CashAccountService.test.ts            | 79 +++++--------------
 .../src/CashAccountService.ts                 | 45 ++++-------
 packages/cash-account-service/src/types.ts    |  6 +-
 3 files changed, 36 insertions(+), 94 deletions(-)

diff --git a/packages/cash-account-service/src/CashAccountService.test.ts b/packages/cash-account-service/src/CashAccountService.test.ts
index 041eb846507..d98089f04d2 100644
--- a/packages/cash-account-service/src/CashAccountService.test.ts
+++ b/packages/cash-account-service/src/CashAccountService.test.ts
@@ -1,6 +1,5 @@
 import type { HdKeyring } from '@metamask/eth-hd-keyring';
 import { KeyringTypes } from '@metamask/keyring-controller';
-import type { KeyringObject } from '@metamask/keyring-controller';
 import type {
   MessengerActions,
   MessengerEvents,
@@ -25,18 +24,11 @@ const MOCK_MNEMONIC = new Uint8Array([
 
 const MOCK_ENTROPY_SOURCE = 'mock-entropy-source-id';
 
-const MOCK_HD_KEYRING: KeyringObject = {
-  type: KeyringTypes.hd,
-  accounts: ['0x1234'],
-  metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
-};
-
 function setup(): {
   service: CashAccountService;
   rootMessenger: RootMessenger;
   mocks: {
-    getState: jest.Mock;
-    getKeyringsByType: jest.Mock;
+    withKeyring: jest.Mock;
     addNewKeyring: jest.Mock;
   };
 } {
@@ -53,21 +45,19 @@ function setup(): {
   rootMessenger.delegate({
     messenger,
     actions: [
-      'KeyringController:getState',
-      'KeyringController:getKeyringsByType',
+      'KeyringController:withKeyring',
       'KeyringController:addNewKeyring',
     ],
     events: [],
   });
 
   const mocks = {
-    getState: jest.fn().mockReturnValue({
-      isUnlocked: true,
-      keyrings: [MOCK_HD_KEYRING],
+    withKeyring: jest.fn().mockImplementation(async (_selector, operation) => {
+      return operation({
+        keyring: { mnemonic: MOCK_MNEMONIC } as unknown as HdKeyring,
+        metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+      });
     }),
-    getKeyringsByType: jest
-      .fn()
-      .mockReturnValue([{ mnemonic: MOCK_MNEMONIC } as unknown as HdKeyring]),
     addNewKeyring: jest.fn().mockResolvedValue({
       id: 'new-cash-keyring-id',
       name: '',
@@ -75,12 +65,8 @@ function setup(): {
   };
 
   rootMessenger.registerActionHandler(
-    'KeyringController:getState',
-    mocks.getState,
-  );
-  rootMessenger.registerActionHandler(
-    'KeyringController:getKeyringsByType',
-    mocks.getKeyringsByType,
+    'KeyringController:withKeyring',
+    mocks.withKeyring,
   );
   rootMessenger.registerActionHandler(
     'KeyringController:addNewKeyring',
@@ -99,7 +85,10 @@ describe('CashAccountService', () => {
 
       const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
 
-      expect(mocks.getKeyringsByType).toHaveBeenCalledWith(KeyringTypes.hd);
+      expect(mocks.withKeyring).toHaveBeenCalledWith(
+        { id: MOCK_ENTROPY_SOURCE },
+        expect.any(Function),
+      );
       expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.cash, {
         mnemonic: MOCK_MNEMONIC,
       });
@@ -117,45 +106,15 @@ describe('CashAccountService', () => {
       expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
     });
 
-    it('finds the correct HD keyring when non-HD keyrings precede it', async () => {
-      const { service, mocks } = setup();
-      mocks.getState.mockReturnValue({
-        isUnlocked: true,
-        keyrings: [
-          {
-            type: KeyringTypes.simple,
-            accounts: ['0xabc'],
-            metadata: { id: 'simple-1', name: '' },
-          },
-          MOCK_HD_KEYRING,
-        ],
-      });
-
-      const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
-
-      expect(mocks.getKeyringsByType).toHaveBeenCalledWith(KeyringTypes.hd);
-      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.cash, {
-        mnemonic: MOCK_MNEMONIC,
-      });
-      expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
-    });
-
-    it('throws if no HD keyring matches the entropy source', async () => {
-      const { service } = setup();
-
-      await expect(
-        service.createCashAccount('nonexistent-entropy-source'),
-      ).rejects.toThrow(
-        'No HD keyring found for entropy source: nonexistent-entropy-source',
-      );
-    });
-
     it('throws if the HD keyring has no mnemonic', async () => {
       const { service, mocks } = setup();
 
-      mocks.getKeyringsByType.mockReturnValue([
-        { mnemonic: null } as unknown as HdKeyring,
-      ]);
+      mocks.withKeyring.mockImplementation(async (_selector, operation) => {
+        return operation({
+          keyring: { mnemonic: null } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
 
       await expect(
         service.createCashAccount(MOCK_ENTROPY_SOURCE),
diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/cash-account-service/src/CashAccountService.ts
index f3dd1cd57c3..661a2693b22 100644
--- a/packages/cash-account-service/src/CashAccountService.ts
+++ b/packages/cash-account-service/src/CashAccountService.ts
@@ -1,9 +1,6 @@
 import type { HdKeyring } from '@metamask/eth-hd-keyring';
 import { KeyringTypes } from '@metamask/keyring-controller';
-import type {
-  KeyringMetadata,
-  KeyringObject,
-} from '@metamask/keyring-controller';
+import type { KeyringMetadata } from '@metamask/keyring-controller';
 
 import type { CashAccountServiceMessenger } from './types';
 
@@ -33,36 +30,24 @@ export class CashAccountService {
    * @returns The metadata of the newly created Cash keyring.
    */
   async createCashAccount(entropySource: string): Promise<KeyringMetadata> {
-    const { keyrings } = this.#messenger.call('KeyringController:getState');
-
-    const hdKeyringsFromState = keyrings.filter(
-      (kr: KeyringObject) => kr.type === KeyringTypes.hd,
-    );
-    const hdKeyringIndex = hdKeyringsFromState.findIndex(
-      (kr: KeyringObject) => kr.metadata.id === entropySource,
-    );
-    if (hdKeyringIndex === -1) {
-      throw new Error(
-        `No HD keyring found for entropy source: ${entropySource}`,
-      );
-    }
-
-    const hdKeyrings = this.#messenger.call(
-      'KeyringController:getKeyringsByType',
-      KeyringTypes.hd,
-    ) as HdKeyring[];
-
-    const hdKeyring = hdKeyrings[hdKeyringIndex];
-    if (!hdKeyring?.mnemonic) {
-      throw new Error(
-        'HD keyring does not have a mnemonic for the given entropy source.',
-      );
-    }
+    const mnemonic = (await this.#messenger.call(
+      'KeyringController:withKeyring',
+      { id: entropySource },
+      async ({ keyring }) => {
+        const hdKeyring = keyring as unknown as HdKeyring;
+        if (!hdKeyring.mnemonic) {
+          throw new Error(
+            'HD keyring does not have a mnemonic for the given entropy source.',
+          );
+        }
+        return hdKeyring.mnemonic;
+      },
+    )) as Uint8Array;
 
     return await this.#messenger.call(
       'KeyringController:addNewKeyring',
       KeyringTypes.cash,
-      { mnemonic: hdKeyring.mnemonic },
+      { mnemonic },
     );
   }
 }
diff --git a/packages/cash-account-service/src/types.ts b/packages/cash-account-service/src/types.ts
index cc1a3ded936..741bd737a51 100644
--- a/packages/cash-account-service/src/types.ts
+++ b/packages/cash-account-service/src/types.ts
@@ -1,7 +1,6 @@
 import type {
   KeyringControllerAddNewKeyringAction,
-  KeyringControllerGetKeyringsByTypeAction,
-  KeyringControllerGetStateAction,
+  KeyringControllerWithKeyringAction,
 } from '@metamask/keyring-controller';
 import type { Messenger } from '@metamask/messenger';
 
@@ -11,8 +10,7 @@ import type { CashAccountServiceMethodActions } from './CashAccountService-metho
 export type CashAccountServiceActions = CashAccountServiceMethodActions;
 
 type AllowedActions =
-  | KeyringControllerGetStateAction
-  | KeyringControllerGetKeyringsByTypeAction
+  | KeyringControllerWithKeyringAction
   | KeyringControllerAddNewKeyringAction;
 
 type AllowedEvents = never;

From c4a966af438eeda32b0503906c79c5146be4d6d5 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Tue, 17 Mar 2026 13:35:27 +0000
Subject: [PATCH 07/29] chore: update team.json

---
 teams.json | 1 +
 1 file changed, 1 insertion(+)

diff --git a/teams.json b/teams.json
index 4a3f6902d14..f5292410e08 100644
--- a/teams.json
+++ b/teams.json
@@ -40,6 +40,7 @@
   "metamask/base-controller": "team-core-platform",
   "metamask/base-data-service": "team-core-platform",
   "metamask/build-utils": "team-core-platform",
+  "metamask/cash-account-service": "team-earn",
   "metamask/composable-controller": "team-core-platform",
   "metamask/connectivity-controller": "team-core-platform",
   "metamask/geolocation-controller": "team-core-platform",

From 9a8489e85dded2ba679b6ac356378f70480b35f9 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 13:16:01 +0000
Subject: [PATCH 08/29] chore: add the cash keyring to the accounts controller
 switch

---
 packages/accounts-controller/src/AccountsController.test.ts | 1 +
 packages/accounts-controller/src/utils.ts                   | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/packages/accounts-controller/src/AccountsController.test.ts b/packages/accounts-controller/src/AccountsController.test.ts
index 2b56924135a..a8f2e49c3f5 100644
--- a/packages/accounts-controller/src/AccountsController.test.ts
+++ b/packages/accounts-controller/src/AccountsController.test.ts
@@ -2726,6 +2726,7 @@ describe('AccountsController', () => {
       KeyringTypes.ledger,
       KeyringTypes.lattice,
       KeyringTypes.qr,
+      KeyringTypes.cash,
     ])('should add accounts for %s type', async (keyringType) => {
       mockUUIDWithNormalAccounts([mockAccount]);
 
diff --git a/packages/accounts-controller/src/utils.ts b/packages/accounts-controller/src/utils.ts
index 5620031d37b..8c4f882f48e 100644
--- a/packages/accounts-controller/src/utils.ts
+++ b/packages/accounts-controller/src/utils.ts
@@ -39,6 +39,9 @@ export function keyringTypeToName(keyringType: string): string {
     case KeyringTypes.qr: {
       return 'QR';
     }
+    case KeyringTypes.cash: {
+      return 'Cash Account';
+    }
     case KeyringTypes.snap: {
       return 'Snap Account';
     }

From ccc6c2c8cdf2792925602111733bb89f3f4bfcfc Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 13:56:46 +0000
Subject: [PATCH 09/29] fix: make createAccount idempotent

---
 packages/cash-account-service/package.json    |  3 +-
 .../src/CashAccountService.test.ts            | 41 +++++++++++++++++--
 .../src/CashAccountService.ts                 | 25 ++++++++++-
 3 files changed, 62 insertions(+), 7 deletions(-)

diff --git a/packages/cash-account-service/package.json b/packages/cash-account-service/package.json
index 5d924c899cc..8bb5088d782 100644
--- a/packages/cash-account-service/package.json
+++ b/packages/cash-account-service/package.json
@@ -49,8 +49,7 @@
   "dependencies": {
     "@metamask/base-controller": "^9.0.0",
     "@metamask/keyring-controller": "^25.1.0",
-    "@metamask/messenger": "^0.3.0",
-    "@metamask/utils": "^11.9.0"
+    "@metamask/messenger": "^0.3.0"
   },
   "devDependencies": {
     "@metamask/auto-changelog": "^3.4.4",
diff --git a/packages/cash-account-service/src/CashAccountService.test.ts b/packages/cash-account-service/src/CashAccountService.test.ts
index d98089f04d2..f7a1bf4c4dc 100644
--- a/packages/cash-account-service/src/CashAccountService.test.ts
+++ b/packages/cash-account-service/src/CashAccountService.test.ts
@@ -52,9 +52,15 @@ function setup(): {
   });
 
   const mocks = {
-    withKeyring: jest.fn().mockImplementation(async (_selector, operation) => {
+    withKeyring: jest.fn().mockImplementation(async (selector, operation) => {
+      if ('type' in selector) {
+        throw new Error('Keyring not found');
+      }
       return operation({
-        keyring: { mnemonic: MOCK_MNEMONIC } as unknown as HdKeyring,
+        keyring: {
+          type: 'HD Key Tree',
+          mnemonic: MOCK_MNEMONIC,
+        } as unknown as HdKeyring,
         metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
       });
     }),
@@ -106,12 +112,41 @@ describe('CashAccountService', () => {
       expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
     });
 
+    it('returns existing cash keyring metadata if a cash account already exists', async () => {
+      const { service, mocks } = setup();
+      const MOCK_CASH_METADATA = { id: 'existing-cash-keyring-id', name: '' };
+      const MOCK_CASH_ADDRESS = '0x1234567890abcdef1234567890abcdef12345678';
+
+      mocks.withKeyring.mockImplementation(async (selector, operation) => {
+        if ('type' in selector && selector.type === KeyringTypes.cash) {
+          return operation({
+            keyring: {
+              getAccounts: jest.fn().mockResolvedValue([MOCK_CASH_ADDRESS]),
+            },
+            metadata: MOCK_CASH_METADATA,
+          });
+        }
+        return operation({
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: MOCK_MNEMONIC,
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
+
+      expect(result).toStrictEqual(MOCK_CASH_METADATA);
+      expect(mocks.addNewKeyring).not.toHaveBeenCalled();
+    });
+
     it('throws if the HD keyring has no mnemonic', async () => {
       const { service, mocks } = setup();
 
       mocks.withKeyring.mockImplementation(async (_selector, operation) => {
         return operation({
-          keyring: { mnemonic: null } as unknown as HdKeyring,
+          keyring: { type: 'HD Key Tree', mnemonic: null } as unknown as HdKeyring,
           metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
         });
       });
diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/cash-account-service/src/CashAccountService.ts
index 661a2693b22..87cebf7c888 100644
--- a/packages/cash-account-service/src/CashAccountService.ts
+++ b/packages/cash-account-service/src/CashAccountService.ts
@@ -1,4 +1,4 @@
-import type { HdKeyring } from '@metamask/eth-hd-keyring';
+import { HdKeyring } from '@metamask/eth-hd-keyring';
 import { KeyringTypes } from '@metamask/keyring-controller';
 import type { KeyringMetadata } from '@metamask/keyring-controller';
 
@@ -34,7 +34,13 @@ export class CashAccountService {
       'KeyringController:withKeyring',
       { id: entropySource },
       async ({ keyring }) => {
-        const hdKeyring = keyring as unknown as HdKeyring;
+        if (keyring.type !== HdKeyring.type) {
+          throw new Error(
+            'HD keyring  not have a mnemonic for the given entropy source.',
+          );
+        }
+        const hdKeyring = keyring as HdKeyring;
+
         if (!hdKeyring.mnemonic) {
           throw new Error(
             'HD keyring does not have a mnemonic for the given entropy source.',
@@ -44,6 +50,21 @@ export class CashAccountService {
       },
     )) as Uint8Array;
 
+    const existingCashMetadata = (await this.#messenger
+      .call(
+        'KeyringController:withKeyring',
+        { type: KeyringTypes.cash },
+        async ({ keyring, metadata }) => {
+          const accounts = await keyring.getAccounts();
+          return accounts.length > 0 ? metadata : null;
+        },
+      )
+      .catch(() => null)) as KeyringMetadata | null;
+
+    if (existingCashMetadata) {
+      return existingCashMetadata;
+    }
+
     return await this.#messenger.call(
       'KeyringController:addNewKeyring',
       KeyringTypes.cash,

From b6529384fc2bc6327afa659e245db12c60aefbce Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 13:57:15 +0000
Subject: [PATCH 10/29] chore: remove uneeded guard

---
 packages/cash-account-service/src/CashAccountService.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/cash-account-service/src/CashAccountService.ts
index 87cebf7c888..b0a292b9769 100644
--- a/packages/cash-account-service/src/CashAccountService.ts
+++ b/packages/cash-account-service/src/CashAccountService.ts
@@ -30,7 +30,7 @@ export class CashAccountService {
    * @returns The metadata of the newly created Cash keyring.
    */
   async createCashAccount(entropySource: string): Promise<KeyringMetadata> {
-    const mnemonic = (await this.#messenger.call(
+    const mnemonic = await this.#messenger.call(
       'KeyringController:withKeyring',
       { id: entropySource },
       async ({ keyring }) => {
@@ -48,7 +48,7 @@ export class CashAccountService {
         }
         return hdKeyring.mnemonic;
       },
-    )) as Uint8Array;
+    );
 
     const existingCashMetadata = (await this.#messenger
       .call(

From 7ac9b62ea0dcfb1c63783eb9e97fd16f065da44f Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 13:57:49 +0000
Subject: [PATCH 11/29] chore: update teams.json

---
 teams.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/teams.json b/teams.json
index f5292410e08..470f0a3e2cb 100644
--- a/teams.json
+++ b/teams.json
@@ -40,7 +40,7 @@
   "metamask/base-controller": "team-core-platform",
   "metamask/base-data-service": "team-core-platform",
   "metamask/build-utils": "team-core-platform",
-  "metamask/cash-account-service": "team-earn",
+  "metamask/cash-account-service": "team-accounts-framework,team-earn",
   "metamask/composable-controller": "team-core-platform",
   "metamask/connectivity-controller": "team-core-platform",
   "metamask/geolocation-controller": "team-core-platform",

From 9b5b9b21e9a6145c353c0e2b49d9ae17d5e904d0 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 13:59:41 +0000
Subject: [PATCH 12/29] chore: update codeowners to make new service shared

---
 .github/CODEOWNERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index 3e10a5b7016..473fe1eb33d 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -117,6 +117,7 @@
 /packages/remote-feature-flag-controller        @MetaMask/extension-platform @MetaMask/mobile-platform @MetaMask/core-platform
 /packages/storage-service                       @MetaMask/extension-platform @MetaMask/mobile-platform @MetaMask/core-platform
 /packages/client-controller                     @MetaMask/core-platform @MetaMask/extension-platform @MetaMask/mobile-platform
+/packages/cash-account-service                  @MetaMask/accounts-engineers @MetaMask/metamask-earn
 
 ## Package Release related
 /packages/account-tree-controller/package.json  @MetaMask/accounts-engineers @MetaMask/core-platform

From 99bc537d839f4d8d9a8f421b02fcf054baef2283 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 14:03:50 +0000
Subject: [PATCH 13/29] chore: updaet changelogs

---
 packages/accounts-controller/CHANGELOG.md  | 1 +
 packages/cash-account-service/CHANGELOG.md | 2 +-
 packages/keyring-controller/CHANGELOG.md   | 5 +++++
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/packages/accounts-controller/CHANGELOG.md b/packages/accounts-controller/CHANGELOG.md
index 6b7a652a219..99ea932288a 100644
--- a/packages/accounts-controller/CHANGELOG.md
+++ b/packages/accounts-controller/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Add support for `KeyringTypes.cash` in `keyringTypeToName`, mapping it to `'Cash Account'` ([#8204](https://github.com/MetaMask/core/pull/8204))
 - Add `:accounts{Added,Removed}` batch events ([#8151](https://github.com/MetaMask/core/pull/8151))
   - Those new events can be used instead of single `:accountAdded` and `:accountRemoved` events to reduce the number of events emitted during batch operations (e.g. `KeyringController` state re-synchronization).
 
diff --git a/packages/cash-account-service/CHANGELOG.md b/packages/cash-account-service/CHANGELOG.md
index 8fcf72c699c..955ecf2e9f9 100644
--- a/packages/cash-account-service/CHANGELOG.md
+++ b/packages/cash-account-service/CHANGELOG.md
@@ -9,6 +9,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- Initial release
+- Initial release ([#8204](https://github.com/MetaMask/core/pull/8204))
 
 [Unreleased]: https://github.com/MetaMask/core/
diff --git a/packages/keyring-controller/CHANGELOG.md b/packages/keyring-controller/CHANGELOG.md
index 073f80166da..6230b47674b 100644
--- a/packages/keyring-controller/CHANGELOG.md
+++ b/packages/keyring-controller/CHANGELOG.md
@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `KeyringTypes.cash` (`'Cash Keyring'`) to the `KeyringTypes` enum ([#8204](https://github.com/MetaMask/core/pull/8204))
+- Add `CashKeyring` (from `@metamask-previews/eth-cash-keyring`) as a built-in default keyring ([#8204](https://github.com/MetaMask/core/pull/8204))
+
 ### Changed
 
 - Bump `@metamask/keyring-api` from `^21.0.0` to `^21.6.0` ([#7857](https://github.com/MetaMask/core/pull/7857), [#8259](https://github.com/MetaMask/core/pull/8259))

From 49cab71105684e9149d9d83f53cfdad23bf39230 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 14:06:53 +0000
Subject: [PATCH 14/29] chore: regenerate lockfile

---
 yarn.lock | 1 -
 1 file changed, 1 deletion(-)

diff --git a/yarn.lock b/yarn.lock
index b6a6e7a59a9..4f15a285aa3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3122,7 +3122,6 @@ __metadata:
     "@metamask/eth-hd-keyring": "npm:^13.0.0"
     "@metamask/keyring-controller": "npm:^25.1.0"
     "@metamask/messenger": "npm:^0.3.0"
-    "@metamask/utils": "npm:^11.9.0"
     "@ts-bridge/cli": "npm:^0.6.4"
     "@types/jest": "npm:^29.5.14"
     deepmerge: "npm:^4.2.2"

From 686bc3a4ebcb67da48c5f41b969229e147380aa7 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 14:44:26 +0000
Subject: [PATCH 15/29] chore: fix formatting

---
 packages/cash-account-service/src/CashAccountService.test.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/cash-account-service/src/CashAccountService.test.ts b/packages/cash-account-service/src/CashAccountService.test.ts
index f7a1bf4c4dc..96da178c8f6 100644
--- a/packages/cash-account-service/src/CashAccountService.test.ts
+++ b/packages/cash-account-service/src/CashAccountService.test.ts
@@ -146,7 +146,10 @@ describe('CashAccountService', () => {
 
       mocks.withKeyring.mockImplementation(async (_selector, operation) => {
         return operation({
-          keyring: { type: 'HD Key Tree', mnemonic: null } as unknown as HdKeyring,
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: null,
+          } as unknown as HdKeyring,
           metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
         });
       });

From 31dcb5b8d0c3dbf2b5e6328b6fdefd6e77f7a5c6 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 15:00:29 +0000
Subject: [PATCH 16/29] chore: fix misleading error message

---
 packages/cash-account-service/src/CashAccountService.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/cash-account-service/src/CashAccountService.ts
index b0a292b9769..0a3c92b9c11 100644
--- a/packages/cash-account-service/src/CashAccountService.ts
+++ b/packages/cash-account-service/src/CashAccountService.ts
@@ -35,9 +35,7 @@ export class CashAccountService {
       { id: entropySource },
       async ({ keyring }) => {
         if (keyring.type !== HdKeyring.type) {
-          throw new Error(
-            'HD keyring  not have a mnemonic for the given entropy source.',
-          );
+          throw new Error('Got keyring without HD Keyring type');
         }
         const hdKeyring = keyring as HdKeyring;
 

From 377d17900bd251587ea77417e104c4a542652b10 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Thu, 19 Mar 2026 16:12:34 +0000
Subject: [PATCH 17/29] chore: properly mark dependency as runtime

---
 packages/cash-account-service/package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/cash-account-service/package.json b/packages/cash-account-service/package.json
index 8bb5088d782..c7a74238623 100644
--- a/packages/cash-account-service/package.json
+++ b/packages/cash-account-service/package.json
@@ -48,12 +48,12 @@
   },
   "dependencies": {
     "@metamask/base-controller": "^9.0.0",
+    "@metamask/eth-hd-keyring": "^13.0.0",
     "@metamask/keyring-controller": "^25.1.0",
     "@metamask/messenger": "^0.3.0"
   },
   "devDependencies": {
     "@metamask/auto-changelog": "^3.4.4",
-    "@metamask/eth-hd-keyring": "^13.0.0",
     "@ts-bridge/cli": "^0.6.4",
     "@types/jest": "^29.5.14",
     "deepmerge": "^4.2.2",

From e257bae1a5e82dcecdd00a4dd33a83f726c06e35 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 10:00:18 +0000
Subject: [PATCH 18/29] chore: change cash to money

---
 .github/CODEOWNERS                            |  8 +-
 packages/accounts-controller/CHANGELOG.md     |  2 +-
 .../src/AccountsController.test.ts            |  2 +-
 packages/accounts-controller/src/utils.ts     |  4 +-
 packages/cash-account-service/README.md       | 17 ----
 .../CashAccountService-method-action-types.ts |  9 --
 packages/cash-account-service/src/index.ts    |  9 --
 packages/keyring-controller/CHANGELOG.md      |  4 +-
 packages/keyring-controller/package.json      |  1 +
 .../src/KeyringController.ts                  |  6 +-
 .../CHANGELOG.md                              |  0
 .../LICENSE                                   |  0
 packages/money-account-service/README.md      | 17 ++++
 .../jest.config.js                            |  0
 .../package.json                              | 10 +-
 ...MoneyAccountService-method-action-types.ts |  9 ++
 .../src/MoneyAccountService.test.ts}          | 95 ++++++++++++++-----
 .../src/MoneyAccountService.ts}               | 28 +++---
 packages/money-account-service/src/index.ts   |  9 ++
 .../src/types.ts                              | 10 +-
 .../tsconfig.build.json                       |  0
 .../tsconfig.json                             |  0
 .../typedoc.json                              |  0
 teams.json                                    |  2 +-
 tsconfig.build.json                           |  2 +-
 yarn.lock                                     | 53 +++++++----
 26 files changed, 177 insertions(+), 120 deletions(-)
 delete mode 100644 packages/cash-account-service/README.md
 delete mode 100644 packages/cash-account-service/src/CashAccountService-method-action-types.ts
 delete mode 100644 packages/cash-account-service/src/index.ts
 rename packages/{cash-account-service => money-account-service}/CHANGELOG.md (100%)
 rename packages/{cash-account-service => money-account-service}/LICENSE (100%)
 create mode 100644 packages/money-account-service/README.md
 rename packages/{cash-account-service => money-account-service}/jest.config.js (100%)
 rename packages/{cash-account-service => money-account-service}/package.json (91%)
 create mode 100644 packages/money-account-service/src/MoneyAccountService-method-action-types.ts
 rename packages/{cash-account-service/src/CashAccountService.test.ts => money-account-service/src/MoneyAccountService.test.ts} (55%)
 rename packages/{cash-account-service/src/CashAccountService.ts => money-account-service/src/MoneyAccountService.ts} (66%)
 create mode 100644 packages/money-account-service/src/index.ts
 rename packages/{cash-account-service => money-account-service}/src/types.ts (52%)
 rename packages/{cash-account-service => money-account-service}/tsconfig.build.json (100%)
 rename packages/{cash-account-service => money-account-service}/tsconfig.json (100%)
 rename packages/{cash-account-service => money-account-service}/typedoc.json (100%)

diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
index 473fe1eb33d..3ba251cca2c 100644
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -38,7 +38,7 @@
 
 ## Earn Team
 /packages/earn-controller                   @MetaMask/metamask-earn
-/packages/cash-account-service              @MetaMask/metamask-earn
+/packages/money-account-service              @MetaMask/metamask-earn
 
 ## Social AI Team
 /packages/ai-controllers                    @MetaMask/social-ai
@@ -117,7 +117,7 @@
 /packages/remote-feature-flag-controller        @MetaMask/extension-platform @MetaMask/mobile-platform @MetaMask/core-platform
 /packages/storage-service                       @MetaMask/extension-platform @MetaMask/mobile-platform @MetaMask/core-platform
 /packages/client-controller                     @MetaMask/core-platform @MetaMask/extension-platform @MetaMask/mobile-platform
-/packages/cash-account-service                  @MetaMask/accounts-engineers @MetaMask/metamask-earn
+/packages/money-account-service                  @MetaMask/accounts-engineers @MetaMask/metamask-earn
 
 ## Package Release related
 /packages/account-tree-controller/package.json  @MetaMask/accounts-engineers @MetaMask/core-platform
@@ -139,8 +139,8 @@
 /packages/assets-controller/package.json          @MetaMask/metamask-assets @MetaMask/core-platform
 /packages/assets-controller/CHANGELOG.md          @MetaMask/metamask-assets @MetaMask/core-platform
 
-/packages/cash-account-service/package.json       @MetaMask/metamask-earn @MetaMask/core-platform
-/packages/cash-account-service/CHANGELOG.md       @MetaMask/metamask-earn @MetaMask/core-platform
+/packages/money-account-service/package.json       @MetaMask/metamask-earn @MetaMask/core-platform
+/packages/money-account-service/CHANGELOG.md       @MetaMask/metamask-earn @MetaMask/core-platform
 /packages/chain-agnostic-permission/package.json  @MetaMask/wallet-integrations @MetaMask/core-platform
 /packages/chain-agnostic-permission/CHANGELOG.md  @MetaMask/wallet-integrations @MetaMask/core-platform
 /packages/config-registry-controller/CHANGELOG.md @MetaMask/networks @MetaMask/core-platform
diff --git a/packages/accounts-controller/CHANGELOG.md b/packages/accounts-controller/CHANGELOG.md
index 99ea932288a..3dad8680186 100644
--- a/packages/accounts-controller/CHANGELOG.md
+++ b/packages/accounts-controller/CHANGELOG.md
@@ -9,7 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- Add support for `KeyringTypes.cash` in `keyringTypeToName`, mapping it to `'Cash Account'` ([#8204](https://github.com/MetaMask/core/pull/8204))
+- Add support for `KeyringTypes.money` in `keyringTypeToName`, mapping it to `'Money Account'` ([#8204](https://github.com/MetaMask/core/pull/8204))
 - Add `:accounts{Added,Removed}` batch events ([#8151](https://github.com/MetaMask/core/pull/8151))
   - Those new events can be used instead of single `:accountAdded` and `:accountRemoved` events to reduce the number of events emitted during batch operations (e.g. `KeyringController` state re-synchronization).
 
diff --git a/packages/accounts-controller/src/AccountsController.test.ts b/packages/accounts-controller/src/AccountsController.test.ts
index a8f2e49c3f5..f71452ad9d4 100644
--- a/packages/accounts-controller/src/AccountsController.test.ts
+++ b/packages/accounts-controller/src/AccountsController.test.ts
@@ -2726,7 +2726,7 @@ describe('AccountsController', () => {
       KeyringTypes.ledger,
       KeyringTypes.lattice,
       KeyringTypes.qr,
-      KeyringTypes.cash,
+      KeyringTypes.money,
     ])('should add accounts for %s type', async (keyringType) => {
       mockUUIDWithNormalAccounts([mockAccount]);
 
diff --git a/packages/accounts-controller/src/utils.ts b/packages/accounts-controller/src/utils.ts
index 8c4f882f48e..fc0ffde28f9 100644
--- a/packages/accounts-controller/src/utils.ts
+++ b/packages/accounts-controller/src/utils.ts
@@ -39,8 +39,8 @@ export function keyringTypeToName(keyringType: string): string {
     case KeyringTypes.qr: {
       return 'QR';
     }
-    case KeyringTypes.cash: {
-      return 'Cash Account';
+    case KeyringTypes.money: {
+      return 'Money Account';
     }
     case KeyringTypes.snap: {
       return 'Snap Account';
diff --git a/packages/cash-account-service/README.md b/packages/cash-account-service/README.md
deleted file mode 100644
index 66994ad4cd6..00000000000
--- a/packages/cash-account-service/README.md
+++ /dev/null
@@ -1,17 +0,0 @@
-# `@metamask/cash-account-service`
-
-Cash account service.
-
-This service provides operations for creating and managing Cash accounts derived from HD keyrings.
-
-## Installation
-
-`yarn add @metamask/cash-account-service`
-
-or
-
-`npm install @metamask/cash-account-service`
-
-## Contributing
-
-This package is part of a monorepo. Instructions for contributing can be found in the [monorepo README](https://github.com/MetaMask/core#readme).
diff --git a/packages/cash-account-service/src/CashAccountService-method-action-types.ts b/packages/cash-account-service/src/CashAccountService-method-action-types.ts
deleted file mode 100644
index cec0dacad8b..00000000000
--- a/packages/cash-account-service/src/CashAccountService-method-action-types.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-import type { CashAccountService } from './CashAccountService';
-
-export type CashAccountServiceCreateCashAccountAction = {
-  type: `CashAccountService:createCashAccount`;
-  handler: CashAccountService['createCashAccount'];
-};
-
-export type CashAccountServiceMethodActions =
-  CashAccountServiceCreateCashAccountAction;
diff --git a/packages/cash-account-service/src/index.ts b/packages/cash-account-service/src/index.ts
deleted file mode 100644
index 46d1826ad6e..00000000000
--- a/packages/cash-account-service/src/index.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-export type {
-  CashAccountServiceActions,
-  CashAccountServiceMessenger,
-} from './types';
-export type {
-  CashAccountServiceCreateCashAccountAction,
-  CashAccountServiceMethodActions,
-} from './CashAccountService-method-action-types';
-export { CashAccountService } from './CashAccountService';
diff --git a/packages/keyring-controller/CHANGELOG.md b/packages/keyring-controller/CHANGELOG.md
index 6230b47674b..997e8807406 100644
--- a/packages/keyring-controller/CHANGELOG.md
+++ b/packages/keyring-controller/CHANGELOG.md
@@ -9,8 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- Add `KeyringTypes.cash` (`'Cash Keyring'`) to the `KeyringTypes` enum ([#8204](https://github.com/MetaMask/core/pull/8204))
-- Add `CashKeyring` (from `@metamask-previews/eth-cash-keyring`) as a built-in default keyring ([#8204](https://github.com/MetaMask/core/pull/8204))
+- Add `KeyringTypes.money` (`'Money Keyring'`) to the `KeyringTypes` enum ([#8204](https://github.com/MetaMask/core/pull/8204))
+- Add `MoneyKeyring` (from `@metamask/eth-money-keyring`) as a built-in default keyring ([#8204](https://github.com/MetaMask/core/pull/8204))
 
 ### Changed
 
diff --git a/packages/keyring-controller/package.json b/packages/keyring-controller/package.json
index d470ee909e1..2b7659e841e 100644
--- a/packages/keyring-controller/package.json
+++ b/packages/keyring-controller/package.json
@@ -52,6 +52,7 @@
     "@metamask/base-controller": "^9.0.0",
     "@metamask/browser-passworder": "^6.0.0",
     "@metamask/eth-hd-keyring": "^13.0.0",
+    "@metamask/eth-money-keyring": "1.0.0",
     "@metamask/eth-sig-util": "^8.2.0",
     "@metamask/eth-simple-keyring": "^11.0.0",
     "@metamask/keyring-api": "^21.6.0",
diff --git a/packages/keyring-controller/src/KeyringController.ts b/packages/keyring-controller/src/KeyringController.ts
index 788ec8a88b5..50807fa7ba0 100644
--- a/packages/keyring-controller/src/KeyringController.ts
+++ b/packages/keyring-controller/src/KeyringController.ts
@@ -3,6 +3,7 @@ import { isValidPrivate, getBinarySize } from '@ethereumjs/util';
 import { BaseController } from '@metamask/base-controller';
 import type * as encryptorUtils from '@metamask/browser-passworder';
 import { HdKeyring } from '@metamask/eth-hd-keyring';
+import { MoneyKeyring } from '@metamask/eth-money-keyring';
 import { normalize as ethNormalize } from '@metamask/eth-sig-util';
 import SimpleKeyring from '@metamask/eth-simple-keyring';
 import type {
@@ -28,7 +29,6 @@ import {
   isValidJson,
   remove0x,
 } from '@metamask/utils';
-import { CashKeyring } from '@metamask-previews/eth-cash-keyring';
 import { Mutex } from 'async-mutex';
 import type { MutexInterface } from 'async-mutex';
 import Wallet, { thirdparty as importers } from 'ethereumjs-wallet';
@@ -56,7 +56,7 @@ export enum KeyringTypes {
   /* eslint-disable @typescript-eslint/naming-convention */
   simple = 'Simple Key Pair',
   hd = 'HD Key Tree',
-  cash = 'Cash Keyring',
+  money = 'Money Keyring',
   qr = 'QR Hardware Wallet Device',
   trezor = 'Trezor Hardware',
   oneKey = 'OneKey Hardware',
@@ -560,7 +560,7 @@ const defaultKeyringBuilders = [
   // @ts-expect-error keyring types are mismatched
   keyringBuilderFactory(SimpleKeyring),
   keyringBuilderFactory(HdKeyring),
-  keyringBuilderFactory(CashKeyring),
+  keyringBuilderFactory(MoneyKeyring),
 ];
 
 export const getDefaultKeyringState = (): KeyringControllerState => {
diff --git a/packages/cash-account-service/CHANGELOG.md b/packages/money-account-service/CHANGELOG.md
similarity index 100%
rename from packages/cash-account-service/CHANGELOG.md
rename to packages/money-account-service/CHANGELOG.md
diff --git a/packages/cash-account-service/LICENSE b/packages/money-account-service/LICENSE
similarity index 100%
rename from packages/cash-account-service/LICENSE
rename to packages/money-account-service/LICENSE
diff --git a/packages/money-account-service/README.md b/packages/money-account-service/README.md
new file mode 100644
index 00000000000..cab3461be6d
--- /dev/null
+++ b/packages/money-account-service/README.md
@@ -0,0 +1,17 @@
+# `@metamask/money-account-service`
+
+Money account service.
+
+This service provides operations for creating and managing Money accounts derived from HD keyrings.
+
+## Installation
+
+`yarn add @metamask/money-account-service`
+
+or
+
+`npm install @metamask/money-account-service`
+
+## Contributing
+
+This package is part of a monorepo. Instructions for contributing can be found in the [monorepo README](https://github.com/MetaMask/core#readme).
diff --git a/packages/cash-account-service/jest.config.js b/packages/money-account-service/jest.config.js
similarity index 100%
rename from packages/cash-account-service/jest.config.js
rename to packages/money-account-service/jest.config.js
diff --git a/packages/cash-account-service/package.json b/packages/money-account-service/package.json
similarity index 91%
rename from packages/cash-account-service/package.json
rename to packages/money-account-service/package.json
index c7a74238623..ac075555bfc 100644
--- a/packages/cash-account-service/package.json
+++ b/packages/money-account-service/package.json
@@ -1,12 +1,12 @@
 {
-  "name": "@metamask/cash-account-service",
+  "name": "@metamask/money-account-service",
   "version": "0.0.0",
-  "description": "Service to manage cash accounts",
+  "description": "Service to manage money accounts",
   "keywords": [
     "MetaMask",
     "Ethereum"
   ],
-  "homepage": "https://github.com/MetaMask/core/tree/main/packages/cash-account-service#readme",
+  "homepage": "https://github.com/MetaMask/core/tree/main/packages/money-account-service#readme",
   "bugs": {
     "url": "https://github.com/MetaMask/core/issues"
   },
@@ -38,8 +38,8 @@
     "build": "ts-bridge --project tsconfig.build.json --verbose --clean --no-references",
     "build:all": "ts-bridge --project tsconfig.build.json --verbose --clean",
     "build:docs": "typedoc",
-    "changelog:update": "../../scripts/update-changelog.sh @metamask/cash-account-service",
-    "changelog:validate": "../../scripts/validate-changelog.sh @metamask/cash-account-service",
+    "changelog:update": "../../scripts/update-changelog.sh @metamask/money-account-service",
+    "changelog:validate": "../../scripts/validate-changelog.sh @metamask/money-account-service",
     "since-latest-release": "../../scripts/since-latest-release.sh",
     "test": "NODE_OPTIONS=--experimental-vm-modules jest --reporters=jest-silent-reporter",
     "test:clean": "NODE_OPTIONS=--experimental-vm-modules jest --clearCache",
diff --git a/packages/money-account-service/src/MoneyAccountService-method-action-types.ts b/packages/money-account-service/src/MoneyAccountService-method-action-types.ts
new file mode 100644
index 00000000000..e2a6d8baea5
--- /dev/null
+++ b/packages/money-account-service/src/MoneyAccountService-method-action-types.ts
@@ -0,0 +1,9 @@
+import type { MoneyAccountService } from './MoneyAccountService';
+
+export type MoneyAccountServiceCreateMoneyAccountAction = {
+  type: `MoneyAccountService:createMoneyAccount`;
+  handler: MoneyAccountService['createMoneyAccount'];
+};
+
+export type MoneyAccountServiceMethodActions =
+  MoneyAccountServiceCreateMoneyAccountAction;
diff --git a/packages/cash-account-service/src/CashAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
similarity index 55%
rename from packages/cash-account-service/src/CashAccountService.test.ts
rename to packages/money-account-service/src/MoneyAccountService.test.ts
index 96da178c8f6..16d2ad32097 100644
--- a/packages/cash-account-service/src/CashAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -7,11 +7,11 @@ import type {
 } from '@metamask/messenger';
 import { Messenger, MOCK_ANY_NAMESPACE } from '@metamask/messenger';
 
-import { CashAccountService, serviceName } from './CashAccountService';
-import type { CashAccountServiceMessenger } from './types';
+import { MoneyAccountService, serviceName } from './MoneyAccountService';
+import type { MoneyAccountServiceMessenger } from './types';
 
-type AllActions = MessengerActions<CashAccountServiceMessenger>;
-type AllEvents = MessengerEvents<CashAccountServiceMessenger>;
+type AllActions = MessengerActions<MoneyAccountServiceMessenger>;
+type AllEvents = MessengerEvents<MoneyAccountServiceMessenger>;
 
 type RootMessenger = Messenger<MockAnyNamespace, AllActions, AllEvents>;
 
@@ -25,7 +25,7 @@ const MOCK_MNEMONIC = new Uint8Array([
 const MOCK_ENTROPY_SOURCE = 'mock-entropy-source-id';
 
 function setup(): {
-  service: CashAccountService;
+  service: MoneyAccountService;
   rootMessenger: RootMessenger;
   mocks: {
     withKeyring: jest.Mock;
@@ -37,7 +37,7 @@ function setup(): {
     captureException: jest.fn(),
   });
 
-  const messenger: CashAccountServiceMessenger = new Messenger({
+  const messenger: MoneyAccountServiceMessenger = new Messenger({
     namespace: serviceName,
     parent: rootMessenger,
   });
@@ -65,7 +65,7 @@ function setup(): {
       });
     }),
     addNewKeyring: jest.fn().mockResolvedValue({
-      id: 'new-cash-keyring-id',
+      id: 'new-money-keyring-id',
       name: '',
     }),
   };
@@ -79,51 +79,51 @@ function setup(): {
     mocks.addNewKeyring,
   );
 
-  const service = new CashAccountService({ messenger });
+  const service = new MoneyAccountService({ messenger });
 
   return { service, rootMessenger, mocks };
 }
 
-describe('CashAccountService', () => {
-  describe('createCashAccount', () => {
-    it('creates a Cash keyring from the HD keyring mnemonic', async () => {
+describe('MoneyAccountService', () => {
+  describe('createMoneyAccount', () => {
+    it('creates a Money keyring from the HD keyring mnemonic', async () => {
       const { service, mocks } = setup();
 
-      const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
+      const result = await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
 
       expect(mocks.withKeyring).toHaveBeenCalledWith(
         { id: MOCK_ENTROPY_SOURCE },
         expect.any(Function),
       );
-      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.cash, {
+      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.money, {
         mnemonic: MOCK_MNEMONIC,
       });
-      expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
+      expect(result).toStrictEqual({ id: 'new-money-keyring-id', name: '' });
     });
 
     it('is callable via the messenger', async () => {
       const { rootMessenger } = setup();
 
       const result = await rootMessenger.call(
-        'CashAccountService:createCashAccount',
+        'MoneyAccountService:createMoneyAccount',
         MOCK_ENTROPY_SOURCE,
       );
 
-      expect(result).toStrictEqual({ id: 'new-cash-keyring-id', name: '' });
+      expect(result).toStrictEqual({ id: 'new-money-keyring-id', name: '' });
     });
 
-    it('returns existing cash keyring metadata if a cash account already exists', async () => {
+    it('returns existing money keyring metadata if a money account already exists', async () => {
       const { service, mocks } = setup();
-      const MOCK_CASH_METADATA = { id: 'existing-cash-keyring-id', name: '' };
-      const MOCK_CASH_ADDRESS = '0x1234567890abcdef1234567890abcdef12345678';
+      const MOCK_MONEY_METADATA = { id: 'existing-money-keyring-id', name: '' };
+      const MOCK_MONEY_ADDRESS = '0x1234567890abcdef1234567890abcdef12345678';
 
       mocks.withKeyring.mockImplementation(async (selector, operation) => {
-        if ('type' in selector && selector.type === KeyringTypes.cash) {
+        if ('type' in selector && selector.type === KeyringTypes.money) {
           return operation({
             keyring: {
-              getAccounts: jest.fn().mockResolvedValue([MOCK_CASH_ADDRESS]),
+              getAccounts: jest.fn().mockResolvedValue([MOCK_MONEY_ADDRESS]),
             },
-            metadata: MOCK_CASH_METADATA,
+            metadata: MOCK_MONEY_METADATA,
           });
         }
         return operation({
@@ -135,12 +135,57 @@ describe('CashAccountService', () => {
         });
       });
 
-      const result = await service.createCashAccount(MOCK_ENTROPY_SOURCE);
+      const result = await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
 
-      expect(result).toStrictEqual(MOCK_CASH_METADATA);
+      expect(result).toStrictEqual(MOCK_MONEY_METADATA);
       expect(mocks.addNewKeyring).not.toHaveBeenCalled();
     });
 
+    it('creates a new money keyring if an existing one has no accounts', async () => {
+      const { service, mocks } = setup();
+
+      mocks.withKeyring.mockImplementation(async (selector, operation) => {
+        if ('type' in selector && selector.type === KeyringTypes.money) {
+          return operation({
+            keyring: {
+              getAccounts: jest.fn().mockResolvedValue([]),
+            },
+            metadata: { id: 'empty-money-keyring-id', name: '' },
+          });
+        }
+        return operation({
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: MOCK_MNEMONIC,
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
+
+      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.money, {
+        mnemonic: MOCK_MNEMONIC,
+      });
+    });
+
+    it('throws if the keyring is not an HD keyring', async () => {
+      const { service, mocks } = setup();
+
+      mocks.withKeyring.mockImplementation(async (_selector, operation) => {
+        return operation({
+          keyring: {
+            type: 'Simple Key Pair',
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      await expect(
+        service.createMoneyAccount(MOCK_ENTROPY_SOURCE),
+      ).rejects.toThrow('Got keyring without HD Keyring type');
+    });
+
     it('throws if the HD keyring has no mnemonic', async () => {
       const { service, mocks } = setup();
 
@@ -155,7 +200,7 @@ describe('CashAccountService', () => {
       });
 
       await expect(
-        service.createCashAccount(MOCK_ENTROPY_SOURCE),
+        service.createMoneyAccount(MOCK_ENTROPY_SOURCE),
       ).rejects.toThrow(
         'HD keyring does not have a mnemonic for the given entropy source.',
       );
diff --git a/packages/cash-account-service/src/CashAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
similarity index 66%
rename from packages/cash-account-service/src/CashAccountService.ts
rename to packages/money-account-service/src/MoneyAccountService.ts
index 0a3c92b9c11..74aac33a5a0 100644
--- a/packages/cash-account-service/src/CashAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -2,18 +2,18 @@ import { HdKeyring } from '@metamask/eth-hd-keyring';
 import { KeyringTypes } from '@metamask/keyring-controller';
 import type { KeyringMetadata } from '@metamask/keyring-controller';
 
-import type { CashAccountServiceMessenger } from './types';
+import type { MoneyAccountServiceMessenger } from './types';
 
-export const serviceName = 'CashAccountService';
+export const serviceName = 'MoneyAccountService';
 
-const MESSENGER_EXPOSED_METHODS = ['createCashAccount'] as const;
+const MESSENGER_EXPOSED_METHODS = ['createMoneyAccount'] as const;
 
-export class CashAccountService {
-  readonly #messenger: CashAccountServiceMessenger;
+export class MoneyAccountService {
+  readonly #messenger: MoneyAccountServiceMessenger;
 
   name: typeof serviceName = serviceName;
 
-  constructor({ messenger }: { messenger: CashAccountServiceMessenger }) {
+  constructor({ messenger }: { messenger: MoneyAccountServiceMessenger }) {
     this.#messenger = messenger;
 
     this.#messenger.registerMethodActionHandlers(
@@ -23,13 +23,13 @@ export class CashAccountService {
   }
 
   /**
-   * Creates a Cash keyring derived from the HD keyring identified by
+   * Creates a Money keyring derived from the HD keyring identified by
    * the given entropy source, and returns the new keyring's metadata.
    *
    * @param entropySource - The metadata id of the HD keyring to derive from.
-   * @returns The metadata of the newly created Cash keyring.
+   * @returns The metadata of the newly created Money keyring.
    */
-  async createCashAccount(entropySource: string): Promise<KeyringMetadata> {
+  async createMoneyAccount(entropySource: string): Promise<KeyringMetadata> {
     const mnemonic = await this.#messenger.call(
       'KeyringController:withKeyring',
       { id: entropySource },
@@ -48,10 +48,10 @@ export class CashAccountService {
       },
     );
 
-    const existingCashMetadata = (await this.#messenger
+    const existingMoneyMetadata = (await this.#messenger
       .call(
         'KeyringController:withKeyring',
-        { type: KeyringTypes.cash },
+        { type: KeyringTypes.money },
         async ({ keyring, metadata }) => {
           const accounts = await keyring.getAccounts();
           return accounts.length > 0 ? metadata : null;
@@ -59,13 +59,13 @@ export class CashAccountService {
       )
       .catch(() => null)) as KeyringMetadata | null;
 
-    if (existingCashMetadata) {
-      return existingCashMetadata;
+    if (existingMoneyMetadata) {
+      return existingMoneyMetadata;
     }
 
     return await this.#messenger.call(
       'KeyringController:addNewKeyring',
-      KeyringTypes.cash,
+      KeyringTypes.money,
       { mnemonic },
     );
   }
diff --git a/packages/money-account-service/src/index.ts b/packages/money-account-service/src/index.ts
new file mode 100644
index 00000000000..a2a7b70590b
--- /dev/null
+++ b/packages/money-account-service/src/index.ts
@@ -0,0 +1,9 @@
+export type {
+  MoneyAccountServiceActions,
+  MoneyAccountServiceMessenger,
+} from './types';
+export type {
+  MoneyAccountServiceCreateMoneyAccountAction,
+  MoneyAccountServiceMethodActions,
+} from './MoneyAccountService-method-action-types';
+export { MoneyAccountService } from './MoneyAccountService';
diff --git a/packages/cash-account-service/src/types.ts b/packages/money-account-service/src/types.ts
similarity index 52%
rename from packages/cash-account-service/src/types.ts
rename to packages/money-account-service/src/types.ts
index 741bd737a51..4b88d643203 100644
--- a/packages/cash-account-service/src/types.ts
+++ b/packages/money-account-service/src/types.ts
@@ -4,10 +4,10 @@ import type {
 } from '@metamask/keyring-controller';
 import type { Messenger } from '@metamask/messenger';
 
-import type { serviceName } from './CashAccountService';
-import type { CashAccountServiceMethodActions } from './CashAccountService-method-action-types';
+import type { serviceName } from './MoneyAccountService';
+import type { MoneyAccountServiceMethodActions } from './MoneyAccountService-method-action-types';
 
-export type CashAccountServiceActions = CashAccountServiceMethodActions;
+export type MoneyAccountServiceActions = MoneyAccountServiceMethodActions;
 
 type AllowedActions =
   | KeyringControllerWithKeyringAction
@@ -15,8 +15,8 @@ type AllowedActions =
 
 type AllowedEvents = never;
 
-export type CashAccountServiceMessenger = Messenger<
+export type MoneyAccountServiceMessenger = Messenger<
   typeof serviceName,
-  CashAccountServiceActions | AllowedActions,
+  MoneyAccountServiceActions | AllowedActions,
   AllowedEvents
 >;
diff --git a/packages/cash-account-service/tsconfig.build.json b/packages/money-account-service/tsconfig.build.json
similarity index 100%
rename from packages/cash-account-service/tsconfig.build.json
rename to packages/money-account-service/tsconfig.build.json
diff --git a/packages/cash-account-service/tsconfig.json b/packages/money-account-service/tsconfig.json
similarity index 100%
rename from packages/cash-account-service/tsconfig.json
rename to packages/money-account-service/tsconfig.json
diff --git a/packages/cash-account-service/typedoc.json b/packages/money-account-service/typedoc.json
similarity index 100%
rename from packages/cash-account-service/typedoc.json
rename to packages/money-account-service/typedoc.json
diff --git a/teams.json b/teams.json
index 470f0a3e2cb..b46adc304a1 100644
--- a/teams.json
+++ b/teams.json
@@ -40,7 +40,7 @@
   "metamask/base-controller": "team-core-platform",
   "metamask/base-data-service": "team-core-platform",
   "metamask/build-utils": "team-core-platform",
-  "metamask/cash-account-service": "team-accounts-framework,team-earn",
+  "metamask/money-account-service": "team-accounts-framework,team-earn",
   "metamask/composable-controller": "team-core-platform",
   "metamask/connectivity-controller": "team-core-platform",
   "metamask/geolocation-controller": "team-core-platform",
diff --git a/tsconfig.build.json b/tsconfig.build.json
index 546267cfba1..e3894a87f0d 100644
--- a/tsconfig.build.json
+++ b/tsconfig.build.json
@@ -56,7 +56,7 @@
       "path": "./packages/build-utils/tsconfig.build.json"
     },
     {
-      "path": "./packages/cash-account-service/tsconfig.build.json"
+      "path": "./packages/money-account-service/tsconfig.build.json"
     },
     {
       "path": "./packages/chain-agnostic-permission/tsconfig.build.json"
diff --git a/yarn.lock b/yarn.lock
index 4f15a285aa3..779ba9c3aee 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3113,26 +3113,6 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@metamask/cash-account-service@workspace:packages/cash-account-service":
-  version: 0.0.0-use.local
-  resolution: "@metamask/cash-account-service@workspace:packages/cash-account-service"
-  dependencies:
-    "@metamask/auto-changelog": "npm:^3.4.4"
-    "@metamask/base-controller": "npm:^9.0.0"
-    "@metamask/eth-hd-keyring": "npm:^13.0.0"
-    "@metamask/keyring-controller": "npm:^25.1.0"
-    "@metamask/messenger": "npm:^0.3.0"
-    "@ts-bridge/cli": "npm:^0.6.4"
-    "@types/jest": "npm:^29.5.14"
-    deepmerge: "npm:^4.2.2"
-    jest: "npm:^29.7.0"
-    ts-jest: "npm:^29.2.5"
-    typedoc: "npm:^0.25.13"
-    typedoc-plugin-missing-exports: "npm:^2.0.0"
-    typescript: "npm:~5.3.3"
-  languageName: unknown
-  linkType: soft
-
 "@metamask/chain-agnostic-permission@npm:^1.4.0, @metamask/chain-agnostic-permission@workspace:packages/chain-agnostic-permission":
   version: 0.0.0-use.local
   resolution: "@metamask/chain-agnostic-permission@workspace:packages/chain-agnostic-permission"
@@ -3702,7 +3682,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@metamask/eth-hd-keyring@npm:13.1.0, @metamask/eth-hd-keyring@npm:^13.0.0":
+"@metamask/eth-hd-keyring@npm:13.1.0, @metamask/eth-hd-keyring@npm:^13.0.0, @metamask/eth-hd-keyring@npm:^13.1.0":
   version: 13.1.0
   resolution: "@metamask/eth-hd-keyring@npm:13.1.0"
   dependencies:
@@ -3812,6 +3792,16 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@metamask/eth-money-keyring@npm:1.0.0":
+  version: 1.0.0
+  resolution: "@metamask/eth-money-keyring@npm:1.0.0"
+  dependencies:
+    "@metamask/eth-hd-keyring": "npm:^13.1.0"
+    "@metamask/superstruct": "npm:^3.1.0"
+  checksum: 10/244caa4cba12550bf0cadca4923a5540d40391e9dee940d7fe980bf77d4d08d329825745c97f89fe4909763d6978921f38b6c3f925fab9e0acd969165d5da718
+  languageName: node
+  linkType: hard
+
 "@metamask/eth-query@npm:^4.0.0":
   version: 4.0.0
   resolution: "@metamask/eth-query@npm:4.0.0"
@@ -4237,6 +4227,7 @@ __metadata:
     "@metamask/base-controller": "npm:^9.0.0"
     "@metamask/browser-passworder": "npm:^6.0.0"
     "@metamask/eth-hd-keyring": "npm:^13.0.0"
+    "@metamask/eth-money-keyring": "npm:1.0.0"
     "@metamask/eth-sig-util": "npm:^8.2.0"
     "@metamask/eth-simple-keyring": "npm:^11.0.0"
     "@metamask/keyring-api": "npm:^21.6.0"
@@ -4400,6 +4391,26 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@metamask/money-account-service@workspace:packages/money-account-service":
+  version: 0.0.0-use.local
+  resolution: "@metamask/money-account-service@workspace:packages/money-account-service"
+  dependencies:
+    "@metamask/auto-changelog": "npm:^3.4.4"
+    "@metamask/base-controller": "npm:^9.0.0"
+    "@metamask/eth-hd-keyring": "npm:^13.0.0"
+    "@metamask/keyring-controller": "npm:^25.1.0"
+    "@metamask/messenger": "npm:^0.3.0"
+    "@ts-bridge/cli": "npm:^0.6.4"
+    "@types/jest": "npm:^29.5.14"
+    deepmerge: "npm:^4.2.2"
+    jest: "npm:^29.7.0"
+    ts-jest: "npm:^29.2.5"
+    typedoc: "npm:^0.25.13"
+    typedoc-plugin-missing-exports: "npm:^2.0.0"
+    typescript: "npm:~5.3.3"
+  languageName: unknown
+  linkType: soft
+
 "@metamask/multichain-account-service@npm:^7.1.0, @metamask/multichain-account-service@workspace:packages/multichain-account-service":
   version: 0.0.0-use.local
   resolution: "@metamask/multichain-account-service@workspace:packages/multichain-account-service"

From c53287500213fa5d33861101e3d2bda75c9103b6 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 10:38:05 +0000
Subject: [PATCH 19/29] feat: check that we see a not found error else rethrow

---
 packages/keyring-controller/CHANGELOG.md      |  1 +
 packages/keyring-controller/src/index.ts      |  1 +
 packages/money-account-service/CHANGELOG.md   |  1 +
 .../src/MoneyAccountService.test.ts           | 32 +++++++++++++++++--
 .../src/MoneyAccountService.ts                | 16 ++++++++--
 5 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/packages/keyring-controller/CHANGELOG.md b/packages/keyring-controller/CHANGELOG.md
index 997e8807406..5373aacec64 100644
--- a/packages/keyring-controller/CHANGELOG.md
+++ b/packages/keyring-controller/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Add `KeyringTypes.money` (`'Money Keyring'`) to the `KeyringTypes` enum ([#8204](https://github.com/MetaMask/core/pull/8204))
 - Add `MoneyKeyring` (from `@metamask/eth-money-keyring`) as a built-in default keyring ([#8204](https://github.com/MetaMask/core/pull/8204))
+- Export `KeyringControllerErrorMessage` enum to allow consumers to distinguish specific controller error cases ([#8204](https://github.com/MetaMask/core/pull/8204))
 
 ### Changed
 
diff --git a/packages/keyring-controller/src/index.ts b/packages/keyring-controller/src/index.ts
index 341ad18bac3..68f49dad764 100644
--- a/packages/keyring-controller/src/index.ts
+++ b/packages/keyring-controller/src/index.ts
@@ -1,3 +1,4 @@
 export * from './KeyringController';
 export type * from './types';
 export * from './errors';
+export { KeyringControllerErrorMessage } from './constants';
diff --git a/packages/money-account-service/CHANGELOG.md b/packages/money-account-service/CHANGELOG.md
index 955ecf2e9f9..f9428bc7cd1 100644
--- a/packages/money-account-service/CHANGELOG.md
+++ b/packages/money-account-service/CHANGELOG.md
@@ -11,4 +11,5 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Initial release ([#8204](https://github.com/MetaMask/core/pull/8204))
 
+### Fixed
 [Unreleased]: https://github.com/MetaMask/core/
diff --git a/packages/money-account-service/src/MoneyAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
index 16d2ad32097..772f9ec6a41 100644
--- a/packages/money-account-service/src/MoneyAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -1,5 +1,9 @@
 import type { HdKeyring } from '@metamask/eth-hd-keyring';
-import { KeyringTypes } from '@metamask/keyring-controller';
+import {
+  KeyringControllerError,
+  KeyringControllerErrorMessage,
+  KeyringTypes,
+} from '@metamask/keyring-controller';
 import type {
   MessengerActions,
   MessengerEvents,
@@ -54,7 +58,9 @@ function setup(): {
   const mocks = {
     withKeyring: jest.fn().mockImplementation(async (selector, operation) => {
       if ('type' in selector) {
-        throw new Error('Keyring not found');
+        throw new KeyringControllerError(
+          KeyringControllerErrorMessage.KeyringNotFound,
+        );
       }
       return operation({
         keyring: {
@@ -169,6 +175,28 @@ describe('MoneyAccountService', () => {
       });
     });
 
+    it('re-throws errors other than KeyringNotFound when checking for an existing money keyring', async () => {
+      const { service, mocks } = setup();
+      const unexpectedError = new KeyringControllerError('Unexpected error');
+
+      mocks.withKeyring.mockImplementation(async (selector, operation) => {
+        if ('type' in selector && selector.type === KeyringTypes.money) {
+          throw unexpectedError;
+        }
+        return operation({
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: MOCK_MNEMONIC,
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      await expect(
+        service.createMoneyAccount(MOCK_ENTROPY_SOURCE),
+      ).rejects.toThrow(unexpectedError);
+    });
+
     it('throws if the keyring is not an HD keyring', async () => {
       const { service, mocks } = setup();
 
diff --git a/packages/money-account-service/src/MoneyAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
index 74aac33a5a0..ab8da119e02 100644
--- a/packages/money-account-service/src/MoneyAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -1,5 +1,9 @@
 import { HdKeyring } from '@metamask/eth-hd-keyring';
-import { KeyringTypes } from '@metamask/keyring-controller';
+import {
+  KeyringControllerError,
+  KeyringControllerErrorMessage,
+  KeyringTypes,
+} from '@metamask/keyring-controller';
 import type { KeyringMetadata } from '@metamask/keyring-controller';
 
 import type { MoneyAccountServiceMessenger } from './types';
@@ -57,7 +61,15 @@ export class MoneyAccountService {
           return accounts.length > 0 ? metadata : null;
         },
       )
-      .catch(() => null)) as KeyringMetadata | null;
+      .catch((error: unknown) => {
+        if (
+          error instanceof KeyringControllerError &&
+          error.message === KeyringControllerErrorMessage.KeyringNotFound
+        ) {
+          return null;
+        }
+        throw error;
+      })) as KeyringMetadata | null;
 
     if (existingMoneyMetadata) {
       return existingMoneyMetadata;

From ad6b7e1316cf5f0698d763426fe3ed4dff1b32cc Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 11:25:35 +0000
Subject: [PATCH 20/29] fix: only ever create one money account

---
 .../src/MoneyAccountService.test.ts           | 41 ++-----------------
 .../src/MoneyAccountService.ts                | 21 ++++++----
 2 files changed, 15 insertions(+), 47 deletions(-)

diff --git a/packages/money-account-service/src/MoneyAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
index 772f9ec6a41..fec0e108e50 100644
--- a/packages/money-account-service/src/MoneyAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -118,19 +118,12 @@ describe('MoneyAccountService', () => {
       expect(result).toStrictEqual({ id: 'new-money-keyring-id', name: '' });
     });
 
-    it('returns existing money keyring metadata if a money account already exists', async () => {
+    it('returns null if a money account already exists', async () => {
       const { service, mocks } = setup();
-      const MOCK_MONEY_METADATA = { id: 'existing-money-keyring-id', name: '' };
-      const MOCK_MONEY_ADDRESS = '0x1234567890abcdef1234567890abcdef12345678';
 
       mocks.withKeyring.mockImplementation(async (selector, operation) => {
         if ('type' in selector && selector.type === KeyringTypes.money) {
-          return operation({
-            keyring: {
-              getAccounts: jest.fn().mockResolvedValue([MOCK_MONEY_ADDRESS]),
-            },
-            metadata: MOCK_MONEY_METADATA,
-          });
+          return operation();
         }
         return operation({
           keyring: {
@@ -143,38 +136,10 @@ describe('MoneyAccountService', () => {
 
       const result = await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
 
-      expect(result).toStrictEqual(MOCK_MONEY_METADATA);
+      expect(result).toBeNull();
       expect(mocks.addNewKeyring).not.toHaveBeenCalled();
     });
 
-    it('creates a new money keyring if an existing one has no accounts', async () => {
-      const { service, mocks } = setup();
-
-      mocks.withKeyring.mockImplementation(async (selector, operation) => {
-        if ('type' in selector && selector.type === KeyringTypes.money) {
-          return operation({
-            keyring: {
-              getAccounts: jest.fn().mockResolvedValue([]),
-            },
-            metadata: { id: 'empty-money-keyring-id', name: '' },
-          });
-        }
-        return operation({
-          keyring: {
-            type: 'HD Key Tree',
-            mnemonic: MOCK_MNEMONIC,
-          } as unknown as HdKeyring,
-          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
-        });
-      });
-
-      await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
-
-      expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.money, {
-        mnemonic: MOCK_MNEMONIC,
-      });
-    });
-
     it('re-throws errors other than KeyringNotFound when checking for an existing money keyring', async () => {
       const { service, mocks } = setup();
       const unexpectedError = new KeyringControllerError('Unexpected error');
diff --git a/packages/money-account-service/src/MoneyAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
index ab8da119e02..d91b2e28c33 100644
--- a/packages/money-account-service/src/MoneyAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -30,10 +30,14 @@ export class MoneyAccountService {
    * Creates a Money keyring derived from the HD keyring identified by
    * the given entropy source, and returns the new keyring's metadata.
    *
+   * If a keyring already existed, just returns null
+   *
    * @param entropySource - The metadata id of the HD keyring to derive from.
    * @returns The metadata of the newly created Money keyring.
    */
-  async createMoneyAccount(entropySource: string): Promise<KeyringMetadata> {
+  async createMoneyAccount(
+    entropySource: string,
+  ): Promise<KeyringMetadata | null> {
     const mnemonic = await this.#messenger.call(
       'KeyringController:withKeyring',
       { id: entropySource },
@@ -52,13 +56,12 @@ export class MoneyAccountService {
       },
     );
 
-    const existingMoneyMetadata = (await this.#messenger
+    const moneyAccountExists = await this.#messenger
       .call(
         'KeyringController:withKeyring',
         { type: KeyringTypes.money },
-        async ({ keyring, metadata }) => {
-          const accounts = await keyring.getAccounts();
-          return accounts.length > 0 ? metadata : null;
+        async () => {
+          return true;
         },
       )
       .catch((error: unknown) => {
@@ -66,13 +69,13 @@ export class MoneyAccountService {
           error instanceof KeyringControllerError &&
           error.message === KeyringControllerErrorMessage.KeyringNotFound
         ) {
-          return null;
+          return false;
         }
         throw error;
-      })) as KeyringMetadata | null;
+      });
 
-    if (existingMoneyMetadata) {
-      return existingMoneyMetadata;
+    if (moneyAccountExists) {
+      return null;
     }
 
     return await this.#messenger.call(

From b8bdf65f00bf255f22a3eb42f13263582bc24529 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 11:30:13 +0000
Subject: [PATCH 21/29] feat: add getMoneyAccount method to the money service

---
 ...MoneyAccountService-method-action-types.ts |  8 +-
 .../src/MoneyAccountService.test.ts           | 75 +++++++++++++++++++
 .../src/MoneyAccountService.ts                | 28 ++++++-
 3 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/packages/money-account-service/src/MoneyAccountService-method-action-types.ts b/packages/money-account-service/src/MoneyAccountService-method-action-types.ts
index e2a6d8baea5..9e08b81937b 100644
--- a/packages/money-account-service/src/MoneyAccountService-method-action-types.ts
+++ b/packages/money-account-service/src/MoneyAccountService-method-action-types.ts
@@ -5,5 +5,11 @@ export type MoneyAccountServiceCreateMoneyAccountAction = {
   handler: MoneyAccountService['createMoneyAccount'];
 };
 
+export type MoneyAccountServiceGetMoneyAccountAction = {
+  type: `MoneyAccountService:getMoneyAccount`;
+  handler: MoneyAccountService['getMoneyAccount'];
+};
+
 export type MoneyAccountServiceMethodActions =
-  MoneyAccountServiceCreateMoneyAccountAction;
+  | MoneyAccountServiceCreateMoneyAccountAction
+  | MoneyAccountServiceGetMoneyAccountAction;
diff --git a/packages/money-account-service/src/MoneyAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
index fec0e108e50..d8b8e075412 100644
--- a/packages/money-account-service/src/MoneyAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -199,4 +199,79 @@ describe('MoneyAccountService', () => {
       );
     });
   });
+
+  describe('getMoneyAccount', () => {
+    it('returns the money keyring metadata if one exists', async () => {
+      const { service, mocks } = setup();
+      const MOCK_MONEY_METADATA = { id: 'existing-money-keyring-id', name: '' };
+
+      mocks.withKeyring.mockImplementation(async (selector, operation) => {
+        if ('type' in selector && selector.type === KeyringTypes.money) {
+          return operation({
+            keyring: {},
+            metadata: MOCK_MONEY_METADATA,
+          });
+        }
+        return operation({
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: MOCK_MNEMONIC,
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      const result = await service.getMoneyAccount();
+
+      expect(result).toStrictEqual(MOCK_MONEY_METADATA);
+    });
+
+    it('returns null if no money account exists', async () => {
+      const { service } = setup();
+
+      const result = await service.getMoneyAccount();
+
+      expect(result).toBeNull();
+    });
+
+    it('is callable via the messenger', async () => {
+      const { rootMessenger, mocks } = setup();
+      const MOCK_MONEY_METADATA = { id: 'existing-money-keyring-id', name: '' };
+
+      mocks.withKeyring.mockImplementation(async (selector, operation) => {
+        if ('type' in selector && selector.type === KeyringTypes.money) {
+          return operation({
+            keyring: {},
+            metadata: MOCK_MONEY_METADATA,
+          });
+        }
+        return operation({
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: MOCK_MNEMONIC,
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      const result = await rootMessenger.call(
+        'MoneyAccountService:getMoneyAccount',
+      );
+
+      expect(result).toStrictEqual(MOCK_MONEY_METADATA);
+    });
+
+    it('re-throws errors other than KeyringNotFound', async () => {
+      const { service, mocks } = setup();
+      const unexpectedError = new KeyringControllerError('Unexpected error');
+
+      mocks.withKeyring.mockImplementation(async (selector) => {
+        if ('type' in selector && selector.type === KeyringTypes.money) {
+          throw unexpectedError;
+        }
+      });
+
+      await expect(service.getMoneyAccount()).rejects.toThrow(unexpectedError);
+    });
+  });
 });
diff --git a/packages/money-account-service/src/MoneyAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
index d91b2e28c33..7fa97c59f74 100644
--- a/packages/money-account-service/src/MoneyAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -10,7 +10,10 @@ import type { MoneyAccountServiceMessenger } from './types';
 
 export const serviceName = 'MoneyAccountService';
 
-const MESSENGER_EXPOSED_METHODS = ['createMoneyAccount'] as const;
+const MESSENGER_EXPOSED_METHODS = [
+  'createMoneyAccount',
+  'getMoneyAccount',
+] as const;
 
 export class MoneyAccountService {
   readonly #messenger: MoneyAccountServiceMessenger;
@@ -84,4 +87,27 @@ export class MoneyAccountService {
       { mnemonic },
     );
   }
+
+  /**
+   * Returns the Money keyring metadata if one exists, otherwise null.
+   *
+   * @returns The metadata of the Money keyring, or null if none exists.
+   */
+  async getMoneyAccount(): Promise<KeyringMetadata | null> {
+    return (await this.#messenger
+      .call(
+        'KeyringController:withKeyring',
+        { type: KeyringTypes.money },
+        async ({ metadata }) => metadata,
+      )
+      .catch((error: unknown) => {
+        if (
+          error instanceof KeyringControllerError &&
+          error.message === KeyringControllerErrorMessage.KeyringNotFound
+        ) {
+          return null;
+        }
+        throw error;
+      })) as KeyringMetadata | null;
+  }
 }

From 355208d94bd3c6bfc3514f96983df93e7a9aee38 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 11:36:59 +0000
Subject: [PATCH 22/29] fix: lock file and depenendecies after rebase

---
 packages/keyring-controller/package.json |  1 -
 yarn.lock                                | 12 +-----------
 2 files changed, 1 insertion(+), 12 deletions(-)

diff --git a/packages/keyring-controller/package.json b/packages/keyring-controller/package.json
index 2b7659e841e..b7d998edf4b 100644
--- a/packages/keyring-controller/package.json
+++ b/packages/keyring-controller/package.json
@@ -48,7 +48,6 @@
   },
   "dependencies": {
     "@ethereumjs/util": "^9.1.0",
-    "@metamask-previews/eth-cash-keyring": "0.0.0-25e4b24",
     "@metamask/base-controller": "^9.0.0",
     "@metamask/browser-passworder": "^6.0.0",
     "@metamask/eth-hd-keyring": "^13.0.0",
diff --git a/yarn.lock b/yarn.lock
index 779ba9c3aee..6583de74b47 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2485,15 +2485,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@metamask-previews/eth-cash-keyring@npm:0.0.0-25e4b24":
-  version: 0.0.0-25e4b24
-  resolution: "@metamask-previews/eth-cash-keyring@npm:0.0.0-25e4b24"
-  dependencies:
-    "@metamask/eth-hd-keyring": "npm:13.1.0"
-  checksum: 10/468cd1afb1a498406cd2b4dd01f5059fc7313739b30c9ed066789f779dc784b7dc5baee982565da334671700a4f0a0bf2c45818040b7b656452700ff36b1a07b
-  languageName: node
-  linkType: hard
-
 "@metamask/7715-permission-types@npm:^0.5.0":
   version: 0.5.0
   resolution: "@metamask/7715-permission-types@npm:0.5.0"
@@ -3682,7 +3673,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@metamask/eth-hd-keyring@npm:13.1.0, @metamask/eth-hd-keyring@npm:^13.0.0, @metamask/eth-hd-keyring@npm:^13.1.0":
+"@metamask/eth-hd-keyring@npm:^13.0.0, @metamask/eth-hd-keyring@npm:^13.1.0":
   version: 13.1.0
   resolution: "@metamask/eth-hd-keyring@npm:13.1.0"
   dependencies:
@@ -4222,7 +4213,6 @@ __metadata:
     "@ethereumjs/util": "npm:^9.1.0"
     "@lavamoat/allow-scripts": "npm:^3.0.4"
     "@lavamoat/preinstall-always-fail": "npm:^2.1.0"
-    "@metamask-previews/eth-cash-keyring": "npm:0.0.0-25e4b24"
     "@metamask/auto-changelog": "npm:^3.4.4"
     "@metamask/base-controller": "npm:^9.0.0"
     "@metamask/browser-passworder": "npm:^6.0.0"

From 522a7ec3bd33775bd401f121280492896f76f5b7 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 11:42:25 +0000
Subject: [PATCH 23/29] chore: lint money package

---
 packages/money-account-service/CHANGELOG.md |  1 +
 yarn.lock                                   | 19 +------------------
 2 files changed, 2 insertions(+), 18 deletions(-)

diff --git a/packages/money-account-service/CHANGELOG.md b/packages/money-account-service/CHANGELOG.md
index f9428bc7cd1..eeca08c5cb0 100644
--- a/packages/money-account-service/CHANGELOG.md
+++ b/packages/money-account-service/CHANGELOG.md
@@ -12,4 +12,5 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Initial release ([#8204](https://github.com/MetaMask/core/pull/8204))
 
 ### Fixed
+
 [Unreleased]: https://github.com/MetaMask/core/
diff --git a/yarn.lock b/yarn.lock
index 6583de74b47..467fc4d123e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4170,24 +4170,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@metamask/keyring-api@npm:^21.3.0":
-  version: 21.5.0
-  resolution: "@metamask/keyring-api@npm:21.5.0"
-  dependencies:
-    "@ethereumjs/tx": "npm:^5.4.0"
-    "@metamask/eth-sig-util": "npm:^8.2.0"
-    "@metamask/keyring-utils": "npm:^3.2.0"
-    "@metamask/superstruct": "npm:^3.1.0"
-    "@metamask/utils": "npm:^11.1.0"
-    "@types/uuid": "npm:^9.0.8"
-    async-mutex: "npm:^0.5.0"
-    bitcoin-address-validation: "npm:^2.2.3"
-    uuid: "npm:^9.0.1"
-  checksum: 10/a7f2a8c66bc76edabde15b66b80904208b71fd62406ebb91579db4c65d74a8f66db6c610afe265823313df7423b6727a4de03cb1f43e41d840d51a5039f9ef4d
-  languageName: node
-  linkType: hard
-
-"@metamask/keyring-api@npm:^21.4.0, @metamask/keyring-api@npm:^21.6.0":
+"@metamask/keyring-api@npm:^21.3.0, @metamask/keyring-api@npm:^21.4.0, @metamask/keyring-api@npm:^21.6.0":
   version: 21.6.0
   resolution: "@metamask/keyring-api@npm:21.6.0"
   dependencies:

From a23ba718877d628b37783513bc18a0c00b207108 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 12:13:45 +0000
Subject: [PATCH 24/29] chore: fix changelog

---
 packages/money-account-service/CHANGELOG.md | 2 --
 1 file changed, 2 deletions(-)

diff --git a/packages/money-account-service/CHANGELOG.md b/packages/money-account-service/CHANGELOG.md
index eeca08c5cb0..955ecf2e9f9 100644
--- a/packages/money-account-service/CHANGELOG.md
+++ b/packages/money-account-service/CHANGELOG.md
@@ -11,6 +11,4 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Initial release ([#8204](https://github.com/MetaMask/core/pull/8204))
 
-### Fixed
-
 [Unreleased]: https://github.com/MetaMask/core/

From e9620906a9de4fe8d449d8b447a6f0256440876c Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 12:55:25 +0000
Subject: [PATCH 25/29] fix: avoid race condition when creating money keyring

---
 .../src/MoneyAccountService.test.ts           | 42 ++++---------------
 .../src/MoneyAccountService.ts                | 24 +++--------
 packages/money-account-service/src/types.ts   |  4 +-
 3 files changed, 18 insertions(+), 52 deletions(-)

diff --git a/packages/money-account-service/src/MoneyAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
index d8b8e075412..df26854e150 100644
--- a/packages/money-account-service/src/MoneyAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -34,6 +34,7 @@ function setup(): {
   mocks: {
     withKeyring: jest.Mock;
     addNewKeyring: jest.Mock;
+    getState: jest.Mock;
   };
 } {
   const rootMessenger: RootMessenger = new Messenger({
@@ -51,6 +52,7 @@ function setup(): {
     actions: [
       'KeyringController:withKeyring',
       'KeyringController:addNewKeyring',
+      'KeyringController:getState',
     ],
     events: [],
   });
@@ -74,6 +76,7 @@ function setup(): {
       id: 'new-money-keyring-id',
       name: '',
     }),
+    getState: jest.fn().mockReturnValue({ keyrings: [] }),
   };
 
   rootMessenger.registerActionHandler(
@@ -84,6 +87,10 @@ function setup(): {
     'KeyringController:addNewKeyring',
     mocks.addNewKeyring,
   );
+  rootMessenger.registerActionHandler(
+    'KeyringController:getState',
+    mocks.getState,
+  );
 
   const service = new MoneyAccountService({ messenger });
 
@@ -121,17 +128,8 @@ describe('MoneyAccountService', () => {
     it('returns null if a money account already exists', async () => {
       const { service, mocks } = setup();
 
-      mocks.withKeyring.mockImplementation(async (selector, operation) => {
-        if ('type' in selector && selector.type === KeyringTypes.money) {
-          return operation();
-        }
-        return operation({
-          keyring: {
-            type: 'HD Key Tree',
-            mnemonic: MOCK_MNEMONIC,
-          } as unknown as HdKeyring,
-          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
-        });
+      mocks.getState.mockReturnValue({
+        keyrings: [{ type: KeyringTypes.money }],
       });
 
       const result = await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
@@ -140,28 +138,6 @@ describe('MoneyAccountService', () => {
       expect(mocks.addNewKeyring).not.toHaveBeenCalled();
     });
 
-    it('re-throws errors other than KeyringNotFound when checking for an existing money keyring', async () => {
-      const { service, mocks } = setup();
-      const unexpectedError = new KeyringControllerError('Unexpected error');
-
-      mocks.withKeyring.mockImplementation(async (selector, operation) => {
-        if ('type' in selector && selector.type === KeyringTypes.money) {
-          throw unexpectedError;
-        }
-        return operation({
-          keyring: {
-            type: 'HD Key Tree',
-            mnemonic: MOCK_MNEMONIC,
-          } as unknown as HdKeyring,
-          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
-        });
-      });
-
-      await expect(
-        service.createMoneyAccount(MOCK_ENTROPY_SOURCE),
-      ).rejects.toThrow(unexpectedError);
-    });
-
     it('throws if the keyring is not an HD keyring', async () => {
       const { service, mocks } = setup();
 
diff --git a/packages/money-account-service/src/MoneyAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
index 7fa97c59f74..1e7101a7c37 100644
--- a/packages/money-account-service/src/MoneyAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -59,25 +59,13 @@ export class MoneyAccountService {
       },
     );
 
-    const moneyAccountExists = await this.#messenger
-      .call(
-        'KeyringController:withKeyring',
-        { type: KeyringTypes.money },
-        async () => {
-          return true;
-        },
-      )
-      .catch((error: unknown) => {
-        if (
-          error instanceof KeyringControllerError &&
-          error.message === KeyringControllerErrorMessage.KeyringNotFound
-        ) {
-          return false;
-        }
-        throw error;
-      });
+    const { keyrings } = this.#messenger.call('KeyringController:getState');
+
+    const moneyKeyringExists = keyrings.some(
+      (keyring) => keyring.type === KeyringTypes.money,
+    );
 
-    if (moneyAccountExists) {
+    if (moneyKeyringExists) {
       return null;
     }
 
diff --git a/packages/money-account-service/src/types.ts b/packages/money-account-service/src/types.ts
index 4b88d643203..fba68670247 100644
--- a/packages/money-account-service/src/types.ts
+++ b/packages/money-account-service/src/types.ts
@@ -1,6 +1,7 @@
 import type {
   KeyringControllerAddNewKeyringAction,
   KeyringControllerWithKeyringAction,
+  KeyringControllerGetStateAction,
 } from '@metamask/keyring-controller';
 import type { Messenger } from '@metamask/messenger';
 
@@ -11,7 +12,8 @@ export type MoneyAccountServiceActions = MoneyAccountServiceMethodActions;
 
 type AllowedActions =
   | KeyringControllerWithKeyringAction
-  | KeyringControllerAddNewKeyringAction;
+  | KeyringControllerAddNewKeyringAction
+  | KeyringControllerGetStateAction;
 
 type AllowedEvents = never;
 

From 7d53b871b2c2a4ba6780c6a3c1fd57c497ad4a62 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 14:41:51 +0000
Subject: [PATCH 26/29] fix: deserialize mnemonic in money account service

---
 .../money-account-service/src/MoneyAccountService.test.ts  | 1 +
 packages/money-account-service/src/MoneyAccountService.ts  | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/packages/money-account-service/src/MoneyAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
index df26854e150..eb12d5dfd6e 100644
--- a/packages/money-account-service/src/MoneyAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -68,6 +68,7 @@ function setup(): {
         keyring: {
           type: 'HD Key Tree',
           mnemonic: MOCK_MNEMONIC,
+          serialize: jest.fn().mockResolvedValue({ mnemonic: MOCK_MNEMONIC }),
         } as unknown as HdKeyring,
         metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
       });
diff --git a/packages/money-account-service/src/MoneyAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
index 1e7101a7c37..2d9f426be3d 100644
--- a/packages/money-account-service/src/MoneyAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -41,7 +41,7 @@ export class MoneyAccountService {
   async createMoneyAccount(
     entropySource: string,
   ): Promise<KeyringMetadata | null> {
-    const mnemonic = await this.#messenger.call(
+    const mnemonic = (await this.#messenger.call(
       'KeyringController:withKeyring',
       { id: entropySource },
       async ({ keyring }) => {
@@ -55,9 +55,10 @@ export class MoneyAccountService {
             'HD keyring does not have a mnemonic for the given entropy source.',
           );
         }
-        return hdKeyring.mnemonic;
+
+        return (await hdKeyring.serialize()).mnemonic;
       },
-    );
+    )) as number[];
 
     const { keyrings } = this.#messenger.call('KeyringController:getState');
 

From f342399faf8d1380227c38d67d55bbbc2396191e Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 15:38:48 +0000
Subject: [PATCH 27/29] feat: add money account service test that interacts
 with real money keyring

---
 packages/money-account-service/package.json   |  1 +
 .../src/MoneyAccountService.test.ts           | 47 +++++++++++++++++++
 .../src/MoneyAccountService.ts                |  3 +-
 yarn.lock                                     |  3 +-
 4 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/packages/money-account-service/package.json b/packages/money-account-service/package.json
index ac075555bfc..f65d57ef098 100644
--- a/packages/money-account-service/package.json
+++ b/packages/money-account-service/package.json
@@ -49,6 +49,7 @@
   "dependencies": {
     "@metamask/base-controller": "^9.0.0",
     "@metamask/eth-hd-keyring": "^13.0.0",
+    "@metamask/eth-money-keyring": "^1.0.0",
     "@metamask/keyring-controller": "^25.1.0",
     "@metamask/messenger": "^0.3.0"
   },
diff --git a/packages/money-account-service/src/MoneyAccountService.test.ts b/packages/money-account-service/src/MoneyAccountService.test.ts
index eb12d5dfd6e..b7e3374c7e9 100644
--- a/packages/money-account-service/src/MoneyAccountService.test.ts
+++ b/packages/money-account-service/src/MoneyAccountService.test.ts
@@ -1,4 +1,9 @@
 import type { HdKeyring } from '@metamask/eth-hd-keyring';
+import {
+  MoneyKeyring,
+  MONEY_DERIVATION_PATH,
+} from '@metamask/eth-money-keyring';
+import type { MoneyKeyringSerializedState } from '@metamask/eth-money-keyring';
 import {
   KeyringControllerError,
   KeyringControllerErrorMessage,
@@ -111,6 +116,8 @@ describe('MoneyAccountService', () => {
       );
       expect(mocks.addNewKeyring).toHaveBeenCalledWith(KeyringTypes.money, {
         mnemonic: MOCK_MNEMONIC,
+        numberOfAccounts: 1,
+        hdPath: MONEY_DERIVATION_PATH,
       });
       expect(result).toStrictEqual({ id: 'new-money-keyring-id', name: '' });
     });
@@ -156,6 +163,46 @@ describe('MoneyAccountService', () => {
       ).rejects.toThrow('Got keyring without HD Keyring type');
     });
 
+    it('passes params to addNewKeyring that produce a correctly initialized MoneyKeyring', async () => {
+      const { service, mocks } = setup();
+
+      // The real HdKeyring.serialize() returns mnemonic as number[] (via Array.from),
+      // not Uint8Array, so we match that format here for MoneyKeyring.deserialize to accept it.
+      mocks.withKeyring.mockImplementation(async (selector, operation) => {
+        if ('type' in selector) {
+          throw new KeyringControllerError(
+            KeyringControllerErrorMessage.KeyringNotFound,
+          );
+        }
+        return operation({
+          keyring: {
+            type: 'HD Key Tree',
+            mnemonic: MOCK_MNEMONIC,
+            serialize: jest
+              .fn()
+              .mockResolvedValue({ mnemonic: Array.from(MOCK_MNEMONIC) }),
+          } as unknown as HdKeyring,
+          metadata: { id: MOCK_ENTROPY_SOURCE, name: '' },
+        });
+      });
+
+      let capturedOpts: unknown;
+      mocks.addNewKeyring.mockImplementation(async (_type, opts) => {
+        capturedOpts = opts;
+        return { id: 'new-money-keyring-id', name: '' };
+      });
+
+      await service.createMoneyAccount(MOCK_ENTROPY_SOURCE);
+
+      const moneyKeyring = new MoneyKeyring();
+      await moneyKeyring.deserialize(
+        capturedOpts as MoneyKeyringSerializedState,
+      );
+
+      expect(moneyKeyring.hdPath).toBe(MONEY_DERIVATION_PATH);
+      expect(await moneyKeyring.getAccounts()).toHaveLength(1);
+    });
+
     it('throws if the HD keyring has no mnemonic', async () => {
       const { service, mocks } = setup();
 
diff --git a/packages/money-account-service/src/MoneyAccountService.ts b/packages/money-account-service/src/MoneyAccountService.ts
index 2d9f426be3d..e68fdd7e3fe 100644
--- a/packages/money-account-service/src/MoneyAccountService.ts
+++ b/packages/money-account-service/src/MoneyAccountService.ts
@@ -1,4 +1,5 @@
 import { HdKeyring } from '@metamask/eth-hd-keyring';
+import { MONEY_DERIVATION_PATH } from '@metamask/eth-money-keyring';
 import {
   KeyringControllerError,
   KeyringControllerErrorMessage,
@@ -73,7 +74,7 @@ export class MoneyAccountService {
     return await this.#messenger.call(
       'KeyringController:addNewKeyring',
       KeyringTypes.money,
-      { mnemonic },
+      { mnemonic, numberOfAccounts: 1, hdPath: MONEY_DERIVATION_PATH },
     );
   }
 
diff --git a/yarn.lock b/yarn.lock
index 467fc4d123e..3a4681519ec 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3783,7 +3783,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@metamask/eth-money-keyring@npm:1.0.0":
+"@metamask/eth-money-keyring@npm:1.0.0, @metamask/eth-money-keyring@npm:^1.0.0":
   version: 1.0.0
   resolution: "@metamask/eth-money-keyring@npm:1.0.0"
   dependencies:
@@ -4371,6 +4371,7 @@ __metadata:
     "@metamask/auto-changelog": "npm:^3.4.4"
     "@metamask/base-controller": "npm:^9.0.0"
     "@metamask/eth-hd-keyring": "npm:^13.0.0"
+    "@metamask/eth-money-keyring": "npm:^1.0.0"
     "@metamask/keyring-controller": "npm:^25.1.0"
     "@metamask/messenger": "npm:^0.3.0"
     "@ts-bridge/cli": "npm:^0.6.4"

From 04f063ba1836abc05f8dfcad2343127d5c8203f1 Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 16:19:23 +0000
Subject: [PATCH 28/29] chore: add a carat to keyring version in package.json

---
 packages/keyring-controller/package.json | 2 +-
 yarn.lock                                | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/keyring-controller/package.json b/packages/keyring-controller/package.json
index b7d998edf4b..5cf26876dd0 100644
--- a/packages/keyring-controller/package.json
+++ b/packages/keyring-controller/package.json
@@ -51,7 +51,7 @@
     "@metamask/base-controller": "^9.0.0",
     "@metamask/browser-passworder": "^6.0.0",
     "@metamask/eth-hd-keyring": "^13.0.0",
-    "@metamask/eth-money-keyring": "1.0.0",
+    "@metamask/eth-money-keyring": "^1.0.0",
     "@metamask/eth-sig-util": "^8.2.0",
     "@metamask/eth-simple-keyring": "^11.0.0",
     "@metamask/keyring-api": "^21.6.0",
diff --git a/yarn.lock b/yarn.lock
index 3a4681519ec..da160fb29a6 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3783,7 +3783,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@metamask/eth-money-keyring@npm:1.0.0, @metamask/eth-money-keyring@npm:^1.0.0":
+"@metamask/eth-money-keyring@npm:^1.0.0":
   version: 1.0.0
   resolution: "@metamask/eth-money-keyring@npm:1.0.0"
   dependencies:
@@ -4200,7 +4200,7 @@ __metadata:
     "@metamask/base-controller": "npm:^9.0.0"
     "@metamask/browser-passworder": "npm:^6.0.0"
     "@metamask/eth-hd-keyring": "npm:^13.0.0"
-    "@metamask/eth-money-keyring": "npm:1.0.0"
+    "@metamask/eth-money-keyring": "npm:^1.0.0"
     "@metamask/eth-sig-util": "npm:^8.2.0"
     "@metamask/eth-simple-keyring": "npm:^11.0.0"
     "@metamask/keyring-api": "npm:^21.6.0"

From 638782ec77271c77af7c6bd5ec5b7daf50cfd81c Mon Sep 17 00:00:00 2001
From: John Whiles <john.whiles@consensys.net>
Date: Fri, 20 Mar 2026 16:33:20 +0000
Subject: [PATCH 29/29] =?UTF-8?q?fix:=20don=E2=80=99t=20export=20method=20?=
 =?UTF-8?q?action=20type=20from=20money=20service?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 packages/money-account-service/src/index.ts | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/packages/money-account-service/src/index.ts b/packages/money-account-service/src/index.ts
index a2a7b70590b..02f76ce0381 100644
--- a/packages/money-account-service/src/index.ts
+++ b/packages/money-account-service/src/index.ts
@@ -2,8 +2,5 @@ export type {
   MoneyAccountServiceActions,
   MoneyAccountServiceMessenger,
 } from './types';
-export type {
-  MoneyAccountServiceCreateMoneyAccountAction,
-  MoneyAccountServiceMethodActions,
-} from './MoneyAccountService-method-action-types';
+export type { MoneyAccountServiceCreateMoneyAccountAction } from './MoneyAccountService-method-action-types';
 export { MoneyAccountService } from './MoneyAccountService';