diff --git a/.github/workflows/1_create_release_pr.yml b/.github/workflows/1_create_release_pr.yml
index 3ef968d0..a60b92ec 100644
--- a/.github/workflows/1_create_release_pr.yml
+++ b/.github/workflows/1_create_release_pr.yml
@@ -26,7 +26,7 @@ jobs:
       uses: cylc/release-actions/stage-1/sanitize-inputs@v1
 
     - name: Checkout repo
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         ref: ${{ env.BASE_REF }}
         fetch-depth: 0  # need to fetch all commits to check contributors
diff --git a/.github/workflows/2_auto_publish_release.yml b/.github/workflows/2_auto_publish_release.yml
index b1d0d80c..afa27b24 100644
--- a/.github/workflows/2_auto_publish_release.yml
+++ b/.github/workflows/2_auto_publish_release.yml
@@ -21,7 +21,7 @@ jobs:
     steps:
 
     - name: Checkout repo
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         ref: ${{ env.MERGE_SHA }}
 
diff --git a/.github/workflows/shortlog.yml b/.github/workflows/shortlog.yml
index d8da001b..c119e620 100644
--- a/.github/workflows/shortlog.yml
+++ b/.github/workflows/shortlog.yml
@@ -13,7 +13,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 0  # need to fetch all commits to check contributors
 
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index fe9a2f60..48a4a45b 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -19,7 +19,7 @@ jobs:
       PYTEST_ADDOPTS: --cov --cov-append --color=yes
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Configure Python
         uses: actions/setup-python@v4
@@ -47,7 +47,7 @@ jobs:
         run: mypy
 
       - name: Checkout FCM
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: ${{ github.event.inputs.fcm_repo || 'metomi/fcm' }}
           ref: ${{ github.event.inputs.fcm_ref || 'master' }}
diff --git a/.github/workflows/update_copyright.yml b/.github/workflows/update_copyright.yml
index 5be6ad97..15989609 100644
--- a/.github/workflows/update_copyright.yml
+++ b/.github/workflows/update_copyright.yml
@@ -11,7 +11,7 @@ jobs:
     timeout-minutes: 10
     steps:
     - name: Checkout repo
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Configure git
       uses: cylc/release-actions/configure-git@v1