diff --git a/app/graphql/mutations/users/update_organization_pins.rb b/app/graphql/mutations/users/update_organization_pins.rb
new file mode 100644
index 00000000..13b18c0f
--- /dev/null
+++ b/app/graphql/mutations/users/update_organization_pins.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module Mutations
+  module Users
+    class UpdateOrganizationPins < BaseMutation
+      description 'Update pinned organizations for a user.'
+
+      field :user, Types::UserType, null: true, description: 'The updated user.'
+
+      argument :organization_ids,
+               [Types::GlobalIdType[::Organization]],
+               required: true,
+               description: 'Ordered list of organization IDs to pin for the user.'
+
+      def resolve(organization_ids:)
+        organizations = organization_ids.map { |id| SagittariusSchema.object_from_id(id) }
+        if organizations.any?(&:nil?)
+          return { user: nil, errors: [create_error(:organization_not_found, 'Invalid organization with provided id')] }
+        end
+
+        ::Users::UpdateOrganizationPinsService.new(
+          current_authentication,
+          organizations.map(&:id)
+        ).execute.to_mutation_response(success_key: :user)
+      end
+    end
+  end
+end
diff --git a/app/graphql/types/mutation_type.rb b/app/graphql/types/mutation_type.rb
index b3833d21..b49b78b8 100644
--- a/app/graphql/types/mutation_type.rb
+++ b/app/graphql/types/mutation_type.rb
@@ -44,6 +44,7 @@ class MutationType < Types::BaseObject
     mount_mutation Mutations::Users::PasswordResetRequest
     mount_mutation Mutations::Users::PasswordReset
     mount_mutation Mutations::Users::Register
+    mount_mutation Mutations::Users::UpdateOrganizationPins
     mount_mutation Mutations::Users::Update
     mount_mutation Mutations::Echo
   end
diff --git a/app/graphql/types/user_organization_pin_type.rb b/app/graphql/types/user_organization_pin_type.rb
new file mode 100644
index 00000000..8cbc8fb7
--- /dev/null
+++ b/app/graphql/types/user_organization_pin_type.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Types
+  class UserOrganizationPinType < Types::BaseObject
+    description 'Represents a pinned organization of a user'
+
+    authorize :read_user_organization_pin
+
+    field :organization, Types::OrganizationType, null: true, description: 'The pinned organization'
+    field :priority, Integer, null: false, description: 'Ordering priority of the pin'
+    field :user, Types::UserType, null: false, description: 'The user owning this pin'
+
+    id_field UserOrganizationPin
+    timestamps
+  end
+end
diff --git a/app/graphql/types/user_type.rb b/app/graphql/types/user_type.rb
index dce975f2..898bc8d1 100644
--- a/app/graphql/types/user_type.rb
+++ b/app/graphql/types/user_type.rb
@@ -42,6 +42,14 @@ class UserType < Types::BaseObject
           description: 'Identities of this user',
           method: :user_identities
 
+    field :organization_pins, [Types::UserOrganizationPinType],
+          null: false,
+          description: 'Pinned organizations of this user with explicit priority'
+
+    field :pinned_organizations, [Types::OrganizationType],
+          null: false,
+          description: 'Pinned organizations of this user ordered by pin priority'
+
     field :mfa_status, Types::MfaStatusType,
           null: true,
           description: 'Multi-factor authentication status of this user'
@@ -72,5 +80,9 @@ def mfa_status
         backup_codes_count: object.backup_codes.size,
       }
     end
+
+    def organization_pins
+      object.user_organization_pins.order(priority: :asc)
+    end
   end
 end
diff --git a/app/models/audit_event.rb b/app/models/audit_event.rb
index 332d468a..be08a155 100644
--- a/app/models/audit_event.rb
+++ b/app/models/audit_event.rb
@@ -41,6 +41,7 @@ class AuditEvent < ApplicationRecord
     password_reset: 37,
     user_deleted: 38,
     user_created: 39,
+    user_organization_pins_updated: 40,
   }.with_indifferent_access
 
   # rubocop:disable Lint/StructNewOverride
diff --git a/app/models/organization.rb b/app/models/organization.rb
index 90c15354..59aaaae2 100644
--- a/app/models/organization.rb
+++ b/app/models/organization.rb
@@ -3,6 +3,9 @@
 class Organization < ApplicationRecord
   include NamespaceParent
 
+  has_many :user_organization_pins, inverse_of: :organization
+  has_many :pinned_by_users, through: :user_organization_pins, source: :user
+
   validates :name, presence: true,
                    length: { minimum: 3, maximum: 50 },
                    allow_blank: false,
diff --git a/app/models/user.rb b/app/models/user.rb
index f6d24f8b..ba756e5c 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -27,6 +27,8 @@ class User < ApplicationRecord
   has_many :namespaces, through: :namespace_memberships, inverse_of: :users
 
   has_many :user_identities, inverse_of: :user
+  has_many :user_organization_pins, -> { order(priority: :asc) }, inverse_of: :user
+  has_many :pinned_organizations, through: :user_organization_pins, source: :organization
 
   has_one_attached :avatar
 
diff --git a/app/models/user_organization_pin.rb b/app/models/user_organization_pin.rb
new file mode 100644
index 00000000..6a267dbf
--- /dev/null
+++ b/app/models/user_organization_pin.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class UserOrganizationPin < ApplicationRecord
+  belongs_to :user, inverse_of: :user_organization_pins
+  belongs_to :organization, inverse_of: :user_organization_pins
+
+  validates :priority, presence: true,
+                       numericality: { only_integer: true, greater_than_or_equal_to: 0 },
+                       uniqueness: { scope: :user_id }
+  validates :organization_id, uniqueness: { scope: :user_id }
+end
diff --git a/app/policies/user_organization_pin_policy.rb b/app/policies/user_organization_pin_policy.rb
new file mode 100644
index 00000000..bb7033cb
--- /dev/null
+++ b/app/policies/user_organization_pin_policy.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class UserOrganizationPinPolicy < BasePolicy
+  delegate { subject.user }
+
+  condition(:user_is_self) { subject.user_id == user&.id }
+
+  rule { user_is_self }.enable :read_user_organization_pin
+end
diff --git a/app/policies/user_policy.rb b/app/policies/user_policy.rb
index 149c94e3..0096bc50 100644
--- a/app/policies/user_policy.rb
+++ b/app/policies/user_policy.rb
@@ -23,6 +23,7 @@ class UserPolicy < BasePolicy
     enable :read_user_identity
     enable :manage_mfa
     enable :update_user
+    enable :update_user_organization_pin
     enable :update_attachment_avatar
     enable :verify_email
     enable :send_verification_email
diff --git a/app/services/error_code.rb b/app/services/error_code.rb
index 44ab5bdd..68861ebe 100644
--- a/app/services/error_code.rb
+++ b/app/services/error_code.rb
@@ -41,6 +41,7 @@ def self.error_codes
       failed_to_save_valid_backup_code: { description: 'The new backup codes could not be saved' },
       invalid_setting: { description: 'Invalid setting provided' },
       invalid_user: { description: 'The user is invalid because of active model errors' },
+      invalid_user_organization_pin: { description: 'The user organization pin is invalid because of active model errors' },
       invalid_password_repeat: { description: 'The provided password repeat does not match the password' },
       cannot_modify_admin: { description: 'Only administrators can modify admin status of users' },
       cannot_modify_own_admin: { description: 'Users cannot modify their own admin status' },
diff --git a/app/services/namespaces/members/delete_service.rb b/app/services/namespaces/members/delete_service.rb
index f89e9a2e..f3059880 100644
--- a/app/services/namespaces/members/delete_service.rb
+++ b/app/services/namespaces/members/delete_service.rb
@@ -27,6 +27,7 @@ def execute
           end
 
           check_last_administrator(t)
+          remove_organization_pin
 
           AuditService.audit(
             :namespace_member_deleted,
@@ -54,6 +55,15 @@ def check_last_administrator(t)
           )
         end
       end
+
+      def remove_organization_pin
+        return unless namespace_member.namespace.organization_type?
+
+        UserOrganizationPin.where(
+          user: namespace_member.user,
+          organization: namespace_member.namespace.parent
+        ).delete_all
+      end
     end
   end
 end
diff --git a/app/services/users/update_organization_pins_service.rb b/app/services/users/update_organization_pins_service.rb
new file mode 100644
index 00000000..27e650f7
--- /dev/null
+++ b/app/services/users/update_organization_pins_service.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+module Users
+  class UpdateOrganizationPinsService
+    include Sagittarius::Database::Transactional
+
+    attr_reader :current_authentication, :user, :organization_ids
+
+    def initialize(current_authentication, organization_ids)
+      @current_authentication = current_authentication
+      @user = current_authentication.user
+      @organization_ids = organization_ids.uniq
+    end
+
+    def execute
+      unless user && Ability.allowed?(current_authentication, :update_user_organization_pin, user)
+        return ServiceResponse.error(message: 'Missing permission', error_code: :missing_permission)
+      end
+
+      organizations = OrganizationsFinder.new(id: organization_ids, namespace_member_user: user).execute
+      if organizations.count != organization_ids.count
+        return ServiceResponse.error(message: 'Organization not found', error_code: :organization_not_found)
+      end
+
+      transactional do |t|
+        old_pins = user.user_organization_pins.map do |pin|
+          { organization_id: pin.organization_id, priority: pin.priority }
+        end
+
+        UserOrganizationPin.where(user: user).delete_all
+
+        organization_ids.each_with_index do |organization_id, priority|
+          pin = user.user_organization_pins.build(organization_id: organization_id, priority: priority)
+          next if pin.save
+
+          t.rollback_and_return! ServiceResponse.error(
+            message: 'Failed to update user organization pins',
+            error_code: :invalid_user_organization_pin,
+            details: pin.errors
+          )
+        end
+
+        new_pins = user.user_organization_pins.reload.map do |pin|
+          { organization_id: pin.organization_id, priority: pin.priority }
+        end
+
+        AuditService.audit(
+          :user_organization_pins_updated,
+          author_id: current_authentication.user.id,
+          entity: user,
+          target: user,
+          details: { old_pins: old_pins, new_pins: new_pins }
+        )
+
+        ServiceResponse.success(message: 'Updated user organization pins', payload: user)
+      end
+    end
+  end
+end
diff --git a/db/migrate/20260504153000_create_user_organization_pins.rb b/db/migrate/20260504153000_create_user_organization_pins.rb
new file mode 100644
index 00000000..f9b7a491
--- /dev/null
+++ b/db/migrate/20260504153000_create_user_organization_pins.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+class CreateUserOrganizationPins < Code0::ZeroTrack::Database::Migration[1.0]
+  def change
+    create_table :user_organization_pins do |t|
+      t.references :user, null: false, foreign_key: { on_delete: :cascade }, index: false
+      t.references :organization, null: false, foreign_key: { on_delete: :cascade }, index: false
+      t.integer :priority, null: false
+
+      t.index %i[user_id organization_id], unique: true
+      t.index %i[user_id priority], unique: true
+
+      t.timestamps_with_timezone
+    end
+  end
+end
diff --git a/db/schema_migrations/20260504153000 b/db/schema_migrations/20260504153000
new file mode 100644
index 00000000..3585e664
--- /dev/null
+++ b/db/schema_migrations/20260504153000
@@ -0,0 +1 @@
+7cf08006d8ab53c1cea495d14f91286debd633d327ea0dee7148ce805d61c32d
\ No newline at end of file
diff --git a/db/structure.sql b/db/structure.sql
index b5ecde6a..d9e0861a 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -831,6 +831,24 @@ CREATE SEQUENCE user_identities_id_seq
 
 ALTER SEQUENCE user_identities_id_seq OWNED BY user_identities.id;
 
+CREATE TABLE user_organization_pins (
+    id bigint NOT NULL,
+    user_id bigint NOT NULL,
+    organization_id bigint NOT NULL,
+    priority integer NOT NULL,
+    created_at timestamp with time zone NOT NULL,
+    updated_at timestamp with time zone NOT NULL
+);
+
+CREATE SEQUENCE user_organization_pins_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1;
+
+ALTER SEQUENCE user_organization_pins_id_seq OWNED BY user_organization_pins.id;
+
 CREATE TABLE user_sessions (
     id bigint NOT NULL,
     user_id bigint NOT NULL,
@@ -956,6 +974,8 @@ ALTER TABLE ONLY translations ALTER COLUMN id SET DEFAULT nextval('translations_
 
 ALTER TABLE ONLY user_identities ALTER COLUMN id SET DEFAULT nextval('user_identities_id_seq'::regclass);
 
+ALTER TABLE ONLY user_organization_pins ALTER COLUMN id SET DEFAULT nextval('user_organization_pins_id_seq'::regclass);
+
 ALTER TABLE ONLY user_sessions ALTER COLUMN id SET DEFAULT nextval('user_sessions_id_seq'::regclass);
 
 ALTER TABLE ONLY users ALTER COLUMN id SET DEFAULT nextval('users_id_seq'::regclass);
@@ -1098,6 +1118,9 @@ ALTER TABLE ONLY translations
 ALTER TABLE ONLY user_identities
     ADD CONSTRAINT user_identities_pkey PRIMARY KEY (id);
 
+ALTER TABLE ONLY user_organization_pins
+    ADD CONSTRAINT user_organization_pins_pkey PRIMARY KEY (id);
+
 ALTER TABLE ONLY user_sessions
     ADD CONSTRAINT user_sessions_pkey PRIMARY KEY (id);
 
@@ -1256,6 +1279,10 @@ CREATE INDEX index_user_identities_on_user_id ON user_identities USING btree (us
 
 CREATE UNIQUE INDEX index_user_identities_on_user_id_and_provider_id ON user_identities USING btree (user_id, provider_id);
 
+CREATE UNIQUE INDEX index_user_organization_pins_on_user_id_and_organization_id ON user_organization_pins USING btree (user_id, organization_id);
+
+CREATE UNIQUE INDEX index_user_organization_pins_on_user_id_and_priority ON user_organization_pins USING btree (user_id, priority);
+
 CREATE UNIQUE INDEX index_user_sessions_on_token ON user_sessions USING btree (token);
 
 CREATE INDEX index_user_sessions_on_user_id ON user_sessions USING btree (user_id);
@@ -1266,6 +1293,9 @@ CREATE UNIQUE INDEX "index_users_on_LOWER_username" ON users USING btree (lower(
 
 CREATE UNIQUE INDEX index_users_on_totp_secret ON users USING btree (totp_secret) WHERE (totp_secret IS NOT NULL);
 
+ALTER TABLE ONLY user_organization_pins
+    ADD CONSTRAINT fk_rails_036679312e FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE;
+
 ALTER TABLE ONLY node_parameters
     ADD CONSTRAINT fk_rails_0d79310cfa FOREIGN KEY (node_function_id) REFERENCES node_functions(id) ON DELETE CASCADE;
 
@@ -1341,6 +1371,9 @@ ALTER TABLE ONLY flow_types
 ALTER TABLE ONLY namespace_role_project_assignments
     ADD CONSTRAINT fk_rails_69066bda8f FOREIGN KEY (project_id) REFERENCES namespace_projects(id);
 
+ALTER TABLE ONLY user_organization_pins
+    ADD CONSTRAINT fk_rails_6b125cdf79 FOREIGN KEY (organization_id) REFERENCES organizations(id) ON DELETE CASCADE;
+
 ALTER TABLE ONLY namespace_member_roles
     ADD CONSTRAINT fk_rails_6c0d5a04c4 FOREIGN KEY (member_id) REFERENCES namespace_members(id) ON DELETE CASCADE;
 
diff --git a/docs/graphql/enum/errorcodeenum.md b/docs/graphql/enum/errorcodeenum.md
index a471a6d5..4fa34de9 100644
--- a/docs/graphql/enum/errorcodeenum.md
+++ b/docs/graphql/enum/errorcodeenum.md
@@ -52,6 +52,7 @@ Represents the available error responses
 | `INVALID_TOTP_SECRET` | The TOTP secret is invalid or cannot be verified |
 | `INVALID_USER` | The user is invalid because of active model errors |
 | `INVALID_USER_IDENTITY` | The user identity is invalid because of active model errors |
+| `INVALID_USER_ORGANIZATION_PIN` | The user organization pin is invalid because of active model errors |
 | `INVALID_USER_SESSION` | The user session is invalid because of active model errors |
 | `INVALID_VERIFICATION_CODE` | Invalid verification code provided |
 | `IS_PRIMARY_RUNTIME` | This runtime is the primary runtime of a project |
diff --git a/docs/graphql/mutation/usersupdateorganizationpins.md b/docs/graphql/mutation/usersupdateorganizationpins.md
new file mode 100644
index 00000000..362ad73a
--- /dev/null
+++ b/docs/graphql/mutation/usersupdateorganizationpins.md
@@ -0,0 +1,20 @@
+---
+title: usersUpdateOrganizationPins
+---
+
+Update pinned organizations for a user.
+
+## Arguments
+
+| Name | Type | Description |
+|------|------|-------------|
+| `clientMutationId` | [`String`](../scalar/string.md) | A unique identifier for the client performing the mutation. |
+| `organizationIds` | [`[OrganizationID!]!`](../scalar/organizationid.md) | Ordered list of organization IDs to pin for the user. |
+
+## Fields
+
+| Name | Type | Description |
+|------|------|-------------|
+| `clientMutationId` | [`String`](../scalar/string.md) | A unique identifier for the client performing the mutation. |
+| `errors` | [`[Error!]!`](../object/error.md) | Errors encountered during execution of the mutation. |
+| `user` | [`User`](../object/user.md) | The updated user. |
diff --git a/docs/graphql/object/user.md b/docs/graphql/object/user.md
index 0b8f27af..eb096fcc 100644
--- a/docs/graphql/object/user.md
+++ b/docs/graphql/object/user.md
@@ -20,6 +20,8 @@ Represents a user
 | `mfaStatus` | [`MfaStatus`](../object/mfastatus.md) | Multi-factor authentication status of this user |
 | `namespace` | [`Namespace`](../object/namespace.md) | Namespace of this user |
 | `namespaceMemberships` | [`NamespaceMemberConnection!`](../object/namespacememberconnection.md) | Namespace Memberships of this user |
+| `organizationPins` | [`[UserOrganizationPin!]!`](../object/userorganizationpin.md) | Pinned organizations of this user with explicit priority |
+| `pinnedOrganizations` | [`[Organization!]!`](../object/organization.md) | Pinned organizations of this user ordered by pin priority |
 | `readme` | [`String`](../scalar/string.md) | Readme of the user |
 | `sessions` | [`UserSessionConnection!`](../object/usersessionconnection.md) | Sessions of this user |
 | `updatedAt` | [`Time!`](../scalar/time.md) | Time when this User was last updated |
diff --git a/docs/graphql/object/userorganizationpin.md b/docs/graphql/object/userorganizationpin.md
new file mode 100644
index 00000000..3a9954b8
--- /dev/null
+++ b/docs/graphql/object/userorganizationpin.md
@@ -0,0 +1,16 @@
+---
+title: UserOrganizationPin
+---
+
+Represents a pinned organization of a user
+
+## Fields without arguments
+
+| Name | Type | Description |
+|------|------|-------------|
+| `createdAt` | [`Time!`](../scalar/time.md) | Time when this UserOrganizationPin was created |
+| `id` | [`UserOrganizationPinID!`](../scalar/userorganizationpinid.md) | Global ID of this UserOrganizationPin |
+| `organization` | [`Organization`](../object/organization.md) | The pinned organization |
+| `priority` | [`Int!`](../scalar/int.md) | Ordering priority of the pin |
+| `updatedAt` | [`Time!`](../scalar/time.md) | Time when this UserOrganizationPin was last updated |
+| `user` | [`User!`](../object/user.md) | The user owning this pin |
diff --git a/docs/graphql/scalar/userorganizationpinid.md b/docs/graphql/scalar/userorganizationpinid.md
new file mode 100644
index 00000000..bb77ff0d
--- /dev/null
+++ b/docs/graphql/scalar/userorganizationpinid.md
@@ -0,0 +1,5 @@
+---
+title: UserOrganizationPinID
+---
+
+A unique identifier for all UserOrganizationPin entities of the application
diff --git a/spec/factories/user_organization_pins.rb b/spec/factories/user_organization_pins.rb
new file mode 100644
index 00000000..e7c11de4
--- /dev/null
+++ b/spec/factories/user_organization_pins.rb
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+FactoryBot.define do
+  sequence(:user_organization_pin_priority)
+
+  factory :user_organization_pin do
+    user
+    organization
+    priority { generate(:user_organization_pin_priority) }
+  end
+end
diff --git a/spec/factories/users.rb b/spec/factories/users.rb
index 66c26f86..02b762a9 100644
--- a/spec/factories/users.rb
+++ b/spec/factories/users.rb
@@ -21,5 +21,15 @@
     trait :with_namespace do
       after :build, &:ensure_namespace
     end
+
+    trait :with_organization_pins do
+      transient do
+        organization_pins_count { 2 }
+      end
+
+      after :create do |user, evaluator|
+        create_list(:user_organization_pin, evaluator.organization_pins_count, user: user)
+      end
+    end
   end
 end
diff --git a/spec/graphql/mutations/users/update_organization_pins_spec.rb b/spec/graphql/mutations/users/update_organization_pins_spec.rb
new file mode 100644
index 00000000..27054439
--- /dev/null
+++ b/spec/graphql/mutations/users/update_organization_pins_spec.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Mutations::Users::UpdateOrganizationPins do
+  it { expect(described_class.graphql_name).to eq('UsersUpdateOrganizationPins') }
+end
diff --git a/spec/graphql/types/user_organization_pin_type_spec.rb b/spec/graphql/types/user_organization_pin_type_spec.rb
new file mode 100644
index 00000000..267b39a2
--- /dev/null
+++ b/spec/graphql/types/user_organization_pin_type_spec.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe SagittariusSchema.types['UserOrganizationPin'] do
+  let(:fields) do
+    %w[
+      id
+      user
+      organization
+      priority
+      createdAt
+      updatedAt
+    ]
+  end
+
+  it { expect(described_class.graphql_name).to eq('UserOrganizationPin') }
+  it { expect(described_class).to have_graphql_fields(fields) }
+  it { expect(described_class).to require_graphql_authorizations(:read_user_organization_pin) }
+end
diff --git a/spec/graphql/types/user_type_spec.rb b/spec/graphql/types/user_type_spec.rb
index e27bba55..97e31f9c 100644
--- a/spec/graphql/types/user_type_spec.rb
+++ b/spec/graphql/types/user_type_spec.rb
@@ -18,6 +18,8 @@
       emailVerifiedAt
       sessions
       identities
+      organizationPins
+      pinnedOrganizations
       mfaStatus
       userAbilities
       createdAt
diff --git a/spec/models/organization_spec.rb b/spec/models/organization_spec.rb
index b646f519..ccd68b78 100644
--- a/spec/models/organization_spec.rb
+++ b/spec/models/organization_spec.rb
@@ -5,6 +5,11 @@
 RSpec.describe Organization do
   subject { create(:organization) }
 
+  describe 'associations' do
+    it { is_expected.to have_many(:user_organization_pins).inverse_of(:organization) }
+    it { is_expected.to have_many(:pinned_by_users).through(:user_organization_pins).source(:user) }
+  end
+
   describe 'validations' do
     it { is_expected.to validate_presence_of(:name) }
     it { is_expected.to validate_uniqueness_of(:name).case_insensitive }
diff --git a/spec/models/user_organization_pin_spec.rb b/spec/models/user_organization_pin_spec.rb
new file mode 100644
index 00000000..9aad9b7f
--- /dev/null
+++ b/spec/models/user_organization_pin_spec.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe UserOrganizationPin do
+  subject { create(:user_organization_pin) }
+
+  describe 'associations' do
+    it { is_expected.to belong_to(:user).inverse_of(:user_organization_pins) }
+    it { is_expected.to belong_to(:organization).inverse_of(:user_organization_pins) }
+  end
+
+  describe 'validations' do
+    it { is_expected.to validate_numericality_of(:priority).only_integer.is_greater_than_or_equal_to(0) }
+    it { is_expected.to validate_uniqueness_of(:organization_id).scoped_to(:user_id) }
+    it { is_expected.to validate_uniqueness_of(:priority).scoped_to(:user_id) }
+  end
+end
diff --git a/spec/models/user_spec.rb b/spec/models/user_spec.rb
index 51c4cb12..b13b3eca 100644
--- a/spec/models/user_spec.rb
+++ b/spec/models/user_spec.rb
@@ -10,6 +10,8 @@
     it { is_expected.to have_many(:authored_audit_events).class_name('AuditEvent').inverse_of(:author) }
     it { is_expected.to have_many(:namespace_memberships).class_name('NamespaceMember').inverse_of(:user) }
     it { is_expected.to have_many(:namespaces).through(:namespace_memberships).inverse_of(:users) }
+    it { is_expected.to have_many(:user_organization_pins).inverse_of(:user) }
+    it { is_expected.to have_many(:pinned_organizations).through(:user_organization_pins).source(:organization) }
   end
 
   describe 'validations' do
diff --git a/spec/policies/user_organization_pin_policy_spec.rb b/spec/policies/user_organization_pin_policy_spec.rb
new file mode 100644
index 00000000..7fed6e6f
--- /dev/null
+++ b/spec/policies/user_organization_pin_policy_spec.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe UserOrganizationPinPolicy do
+  subject { described_class.new(create_authentication(current_user), user_organization_pin) }
+
+  let(:user_organization_pin) { create(:user_organization_pin) }
+
+  context 'when user owns the pin' do
+    let(:current_user) { user_organization_pin.user }
+
+    it { is_expected.to be_allowed(:read_user_organization_pin) }
+  end
+
+  context 'when user does not own the pin' do
+    let(:current_user) { create(:user) }
+
+    it { is_expected.not_to be_allowed(:read_user_organization_pin) }
+  end
+
+  context 'when user is nil' do
+    let(:current_user) { nil }
+
+    it { is_expected.not_to be_allowed(:read_user_organization_pin) }
+  end
+end
diff --git a/spec/policies/user_policy_spec.rb b/spec/policies/user_policy_spec.rb
index c3a33169..7f0194d0 100644
--- a/spec/policies/user_policy_spec.rb
+++ b/spec/policies/user_policy_spec.rb
@@ -7,15 +7,31 @@
 
   let(:user) { create(:user) }
 
-  context 'when user is present' do
+  context 'when user is self' do
+    let(:current_user) { user }
+
+    it { is_expected.to be_allowed(:read_user) }
+    it { is_expected.to be_allowed(:update_user_organization_pin) }
+  end
+
+  context 'when user is someone else' do
     let(:current_user) { create(:user) }
 
     it { is_expected.to be_allowed(:read_user) }
+    it { is_expected.not_to be_allowed(:update_user_organization_pin) }
+  end
+
+  context 'when user is admin' do
+    let(:current_user) { create(:user, :admin) }
+
+    it { is_expected.to be_allowed(:read_user) }
+    it { is_expected.not_to be_allowed(:update_user_organization_pin) }
   end
 
   context 'when user is nil' do
     let(:current_user) { nil }
 
     it { is_expected.not_to be_allowed(:read_user) }
+    it { is_expected.not_to be_allowed(:update_user_organization_pin) }
   end
 end
diff --git a/spec/requests/graphql/mutation/users/update_organization_pins_spec.rb b/spec/requests/graphql/mutation/users/update_organization_pins_spec.rb
new file mode 100644
index 00000000..51954333
--- /dev/null
+++ b/spec/requests/graphql/mutation/users/update_organization_pins_spec.rb
@@ -0,0 +1,63 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe 'usersUpdateOrganizationPins Mutation' do
+  include GraphqlHelpers
+
+  let(:mutation) do
+    <<~QUERY
+      mutation($input: UsersUpdateOrganizationPinsInput!) {
+        usersUpdateOrganizationPins(input: $input) {
+          #{error_query}
+          user {
+            id
+            organizationPins {
+              priority
+            }
+          }
+        }
+      }
+    QUERY
+  end
+
+  let(:current_user) { create(:user) }
+  let(:organization_a) { create(:organization) }
+  let(:organization_b) { create(:organization) }
+  let(:input) do
+    {
+      organizationIds: [organization_b.to_global_id.to_s, organization_a.to_global_id.to_s],
+    }
+  end
+  let(:variables) { { input: input } }
+
+  before do
+    [organization_a, organization_b].each do |organization|
+      create(:namespace_member, namespace: organization.ensure_namespace, user: current_user)
+    end
+
+    post_graphql mutation, variables: variables, current_user: current_user
+  end
+
+  it 'updates organization pins in requested order' do
+    expect(graphql_data_at(:users_update_organization_pins, :user, :id)).to eq(current_user.to_global_id.to_s)
+
+    pins = current_user.reload.user_organization_pins
+    expect(pins.pluck(:organization_id)).to eq([organization_b.id, organization_a.id])
+    expect(pins.pluck(:priority)).to eq([0, 1])
+  end
+
+  context 'when one organization id is invalid' do
+    let(:input) do
+      {
+        organizationIds: [organization_a.to_global_id.to_s, 'gid://sagittarius/Organization/999999'],
+      }
+    end
+
+    it 'returns an error' do
+      expect(graphql_data_at(:users_update_organization_pins, :user)).to be_nil
+      expect(graphql_data_at(:users_update_organization_pins, :errors,
+                             :error_code)).to include('ORGANIZATION_NOT_FOUND')
+    end
+  end
+end
diff --git a/spec/services/namespaces/members/delete_service_spec.rb b/spec/services/namespaces/members/delete_service_spec.rb
index 4771ebc0..4483a31e 100644
--- a/spec/services/namespaces/members/delete_service_spec.rb
+++ b/spec/services/namespaces/members/delete_service_spec.rb
@@ -92,6 +92,9 @@
 
   context 'when user is a member' do
     let(:current_user) { create(:user) }
+    let!(:organization_pin) do
+      create(:user_organization_pin, user: namespace_member.user, organization: namespace.parent)
+    end
 
     before do
       create(:namespace_member, namespace: namespace, user: current_user)
@@ -101,6 +104,12 @@
     it { is_expected.to be_success }
     it { expect { service_response }.to change { NamespaceMember.count }.by(-1) }
 
+    it do
+      expect { service_response }
+        .to change { UserOrganizationPin.exists?(organization_pin.id) }
+        .from(true).to(false)
+    end
+
     it do
       expect { service_response }.to create_audit_event(
         :namespace_member_deleted,
diff --git a/spec/services/users/update_organization_pins_service_spec.rb b/spec/services/users/update_organization_pins_service_spec.rb
new file mode 100644
index 00000000..45f4ec38
--- /dev/null
+++ b/spec/services/users/update_organization_pins_service_spec.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe Users::UpdateOrganizationPinsService do
+  subject(:service_response) do
+    described_class.new(create_authentication(current_user), organization_ids).execute
+  end
+
+  let(:user) { create(:user) }
+  let(:organization_a) { create(:organization) }
+  let(:organization_b) { create(:organization) }
+  let(:organization_ids) { [organization_b.id, organization_a.id] }
+
+  before do
+    [organization_a, organization_b].each do |organization|
+      create(:namespace_member, namespace: organization.ensure_namespace, user: user)
+    end
+  end
+
+  context 'when current user is missing' do
+    let(:current_user) { nil }
+
+    it { is_expected.to be_error }
+    it { expect(service_response.payload[:error_code]).to eq(:missing_permission) }
+    it { expect { service_response }.not_to create_audit_event }
+  end
+
+  context 'when an organization does not exist' do
+    let(:current_user) { user }
+    let(:organization_ids) { [organization_a.id, 999_999] }
+
+    it { is_expected.to be_error }
+    it { expect(service_response.payload[:error_code]).to eq(:organization_not_found) }
+    it { expect { service_response }.not_to create_audit_event }
+  end
+
+  context 'when input is valid' do
+    let(:current_user) { user }
+
+    before do
+      create(:user_organization_pin, user: user, organization: create(:organization), priority: 0)
+    end
+
+    it { is_expected.to be_success }
+
+    it 'replaces pins in given order with priorities' do
+      service_response
+
+      pins = user.reload.user_organization_pins
+      expect(pins.pluck(:organization_id)).to eq(organization_ids)
+      expect(pins.pluck(:priority)).to eq([0, 1])
+    end
+
+    it 'creates an audit event' do
+      expect { service_response }.to create_audit_event(
+        :user_organization_pins_updated,
+        author_id: current_user.id,
+        entity_type: 'User',
+        target_type: 'User'
+      )
+    end
+  end
+
+  context 'when a pin cannot be saved' do
+    let(:current_user) { user }
+    let(:pins_association) { user.user_organization_pins }
+
+    before do
+      allow(user).to receive(:user_organization_pins).and_return(pins_association)
+      allow(pins_association).to receive(:build).and_wrap_original do |original_method, *args|
+        original_method.call(*args).tap do |pin|
+          allow(pin).to receive(:save).and_return(false)
+        end
+      end
+    end
+
+    it { is_expected.to be_error }
+    it { expect(service_response.payload[:error_code]).to eq(:invalid_user_organization_pin) }
+    it { expect { service_response }.not_to create_audit_event }
+  end
+end