diff --git a/.github/workflows/changelog.yaml b/.github/workflows/changelog.yaml
index 2f014a6..7b35e00 100644
--- a/.github/workflows/changelog.yaml
+++ b/.github/workflows/changelog.yaml
@@ -20,7 +20,7 @@ jobs:
     name: Check changelog is in dedicated commit
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - name: Verify CHANGELOG.md changes are in own commit
@@ -32,7 +32,7 @@ jobs:
     name: Shellcheck
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: Install shellcheck
         run: sudo apt-get install -y shellcheck
       - name: Run shellcheck
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6e90b9f..8dae078 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@ and this project adheres to
 
 ## [Unreleased]
 
+### Infrastructure
+
+- CI: bump actions/checkout from 4 to 6 ([6c9eecd], [#49])
+
 ## [1.4.0] - 2026-02-09
 
 ### Added
@@ -153,6 +157,7 @@ and this project adheres to
 
 <!-- Commit links -->
 
+[6c9eecd]: https://github.com/LeakIX/l9format-python/commit/6c9eecd
 [ac4744e]: https://github.com/LeakIX/l9format-python/commit/ac4744e
 [d554f1e]: https://github.com/LeakIX/l9format-python/commit/d554f1e
 [7f49ff5]: https://github.com/LeakIX/l9format-python/commit/7f49ff5
@@ -236,4 +241,5 @@ and this project adheres to
 [#24]: https://github.com/LeakIX/l9format-python/issues/24
 [#31]: https://github.com/LeakIX/l9format-python/issues/31
 [#32]: https://github.com/LeakIX/l9format-python/issues/32
+[#49]: https://github.com/LeakIX/l9format-python/pull/49
 [#43]: https://github.com/LeakIX/l9format-python/issues/43