diff --git a/.github/workflows/ci_mamba.yml b/.github/workflows/ci_mamba.yml
index d6133185b..6ef5d8cea 100644
--- a/.github/workflows/ci_mamba.yml
+++ b/.github/workflows/ci_mamba.yml
@@ -28,7 +28,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Install tcsh and byacc (Linux)
         if: matrix.os == 'ubuntu-latest'