diff --git a/.github/workflows/create-conda-envs.yml b/.github/workflows/create-conda-envs.yml
index f2f52e140c..7bbe66a80b 100644
--- a/.github/workflows/create-conda-envs.yml
+++ b/.github/workflows/create-conda-envs.yml
@@ -25,7 +25,7 @@ jobs:
         python: [3.7, 3.8, 3.9]
     steps:
       - name: checkout cylc-doc
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: configure python
         uses: actions/setup-python@v5
diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
index ebb3c7f3ba..a020383b4e 100644
--- a/.github/workflows/deploy.yml
+++ b/.github/workflows/deploy.yml
@@ -73,7 +73,7 @@ jobs:
         uses: cylc/release-actions/configure-git@v1
 
       - name: checkout cylc-doc
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: ${{ inputs.cylc-flow-tag }}
           path: docs
@@ -109,7 +109,7 @@ jobs:
           working_directory: ./docs
 
       - name: checkout gh-pages
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: gh-pages
           path: gh-pages
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index 52ade1cd74..623c1c6385 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -67,7 +67,7 @@ jobs:
           python-version: '3.9'
 
       - name: checkout cylc-doc
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: ${{ fromJson(env.META_DICT)[matrix.meta_release]['cylc/cylc-doc'] }}
           path: docs
@@ -93,7 +93,7 @@ jobs:
           metomi_rose_opts: ''
 
       - name: checkout gh-pages branch
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: gh-pages
           path: gh-pages
diff --git a/.github/workflows/shortlog.yml b/.github/workflows/shortlog.yml
index 96c5cd6c15..7a93b06c80 100644
--- a/.github/workflows/shortlog.yml
+++ b/.github/workflows/shortlog.yml
@@ -14,7 +14,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           fetch-depth: 0  # need to fetch all commits to check contributors
 
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 5dd910f070..cff6323129 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -43,7 +43,7 @@ jobs:
             node-version: '16'
 
       - name: checkout cylc-doc
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: install dependencies
         uses: ./.github/actions/install-dependencies
diff --git a/.github/workflows/undeploy.yml b/.github/workflows/undeploy.yml
index 00e3fd269b..3ad0e44c75 100644
--- a/.github/workflows/undeploy.yml
+++ b/.github/workflows/undeploy.yml
@@ -47,12 +47,12 @@ jobs:
         uses: cylc/release-actions/configure-git@v1
 
       - name: checkout cylc-doc
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           path: docs
 
       - name: checkout gh-pages
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: gh-pages
           path: gh-pages
diff --git a/.github/workflows/update_copyright.yml b/.github/workflows/update_copyright.yml
index 1250f08252..ecb3aa4316 100644
--- a/.github/workflows/update_copyright.yml
+++ b/.github/workflows/update_copyright.yml
@@ -29,7 +29,7 @@ jobs:
     steps:
 
       - name: Checkout repo
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Configure git
         uses: cylc/release-actions/configure-git@v1