diff --git a/.github/workflows/ci_pkg-install.yml b/.github/workflows/ci_pkg-install.yml
index f378696..9f8f0ae 100644
--- a/.github/workflows/ci_pkg-install.yml
+++ b/.github/workflows/ci_pkg-install.yml
@@ -18,7 +18,7 @@ jobs:
   pkg-check:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v4
       with:
         python-version: 3.8
@@ -48,7 +48,7 @@ jobs:
         os: [ubuntu-latest, macOS-latest, windows-latest]
         python-version: [3.8]  #, 3.9
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
diff --git a/.github/workflows/ci_schema.yml b/.github/workflows/ci_schema.yml
index f511652..30bd2ab 100644
--- a/.github/workflows/ci_schema.yml
+++ b/.github/workflows/ci_schema.yml
@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Install pkg
       run: pip install check-jsonschema
diff --git a/.github/workflows/ci_testing.yml b/.github/workflows/ci_testing.yml
index 2f273e2..6fccade 100644
--- a/.github/workflows/ci_testing.yml
+++ b/.github/workflows/ci_testing.yml
@@ -28,7 +28,7 @@ jobs:
     timeout-minutes: 25
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v4
       with:
diff --git a/.github/workflows/cleanup-caches.yml b/.github/workflows/cleanup-caches.yml
index ca6d81a..77ad7c6 100644
--- a/.github/workflows/cleanup-caches.yml
+++ b/.github/workflows/cleanup-caches.yml
@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out code
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Cleanup
         run: |
diff --git a/.github/workflows/code-format.yml b/.github/workflows/code-format.yml
index 45ef72b..5745db7 100644
--- a/.github/workflows/code-format.yml
+++ b/.github/workflows/code-format.yml
@@ -15,7 +15,7 @@ jobs:
   pre-commit-check:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         # for private repo - first is the checkout step, which needs to use unlimited fetch depth for pushing
         #with:
         #  fetch-depth: 0
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 56bb4ba..6439e1d 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -24,7 +24,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v2
diff --git a/.github/workflows/pypi-release.yml b/.github/workflows/pypi-release.yml
index f096eec..85dccf1 100644
--- a/.github/workflows/pypi-release.yml
+++ b/.github/workflows/pypi-release.yml
@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v4
       with:
         python-version: 3.8