diff --git a/.github/workflows/ci-additional.yaml b/.github/workflows/ci-additional.yaml
index c1d2d89..2845735 100644
--- a/.github/workflows/ci-additional.yaml
+++ b/.github/workflows/ci-additional.yaml
@@ -20,7 +20,7 @@ jobs:
       run:
         shell: bash -l {0}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Fetch all history for all branches and tags.
 
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index fda9c4d..04a5f0d 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -37,7 +37,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v5
+      uses: actions/checkout@v6
 
     - name: Set environment variables
       run: |
@@ -87,7 +87,7 @@ jobs:
         python-version: ["3.12"]
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v6
       with:
diff --git a/.github/workflows/upstream-dev-ci.yaml b/.github/workflows/upstream-dev-ci.yaml
index 04aea57..82021f4 100644
--- a/.github/workflows/upstream-dev-ci.yaml
+++ b/.github/workflows/upstream-dev-ci.yaml
@@ -37,7 +37,7 @@ jobs:
       matrix:
         python-version: ["3.13"]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Fetch all history for all branches and tags.
       - name: Set up conda environment