diff --git a/.github/workflows/R-CMD-check-wsl.yaml b/.github/workflows/R-CMD-check-wsl.yaml
index 2207d137b..377dc3403 100644
--- a/.github/workflows/R-CMD-check-wsl.yaml
+++ b/.github/workflows/R-CMD-check-wsl.yaml
@@ -36,7 +36,7 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
         if: "!startsWith(github.ref, 'refs/tags/') && github.ref != 'refs/heads/master'"
 
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - uses: r-lib/actions/setup-r@v2
       - uses: r-lib/actions/setup-pandoc@v2
diff --git a/.github/workflows/R-CMD-check.yaml b/.github/workflows/R-CMD-check.yaml
index ac720443b..3373ec5f3 100644
--- a/.github/workflows/R-CMD-check.yaml
+++ b/.github/workflows/R-CMD-check.yaml
@@ -49,7 +49,7 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
         if: "!startsWith(github.ref, 'refs/tags/') && github.ref != 'refs/heads/master'"
 
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - uses: r-lib/actions/setup-r@v2
         with:
diff --git a/.github/workflows/Test-coverage.yaml b/.github/workflows/Test-coverage.yaml
index 79173a88d..89f5ca42b 100644
--- a/.github/workflows/Test-coverage.yaml
+++ b/.github/workflows/Test-coverage.yaml
@@ -41,7 +41,7 @@ jobs:
           workflow: Test-coverage.yaml
         if: "!startsWith(github.ref, 'refs/tags/') && github.ref != 'refs/heads/master'"
 
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
 
       - uses: r-lib/actions/setup-r@v2
       - uses: r-lib/actions/setup-pandoc@v2
diff --git a/.github/workflows/cmdstan-tarball-check.yaml b/.github/workflows/cmdstan-tarball-check.yaml
index f3afc732a..ba7758c37 100644
--- a/.github/workflows/cmdstan-tarball-check.yaml
+++ b/.github/workflows/cmdstan-tarball-check.yaml
@@ -32,7 +32,7 @@ jobs:
       NOT_CRAN: true
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install system dependencies
         if: runner.os == 'Linux'
         run: |