diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index 01956f5183..9cc564f218 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -75,9 +75,7 @@ jobs:
       run: |
         # Skip ABS on 3.9, see https://github.com/zarr-developers/zarr-python/pull/1542/#issuecomment-1945557365 etc.
         if [[ "${{ matrix.python-version }}" == '3.9' ]]; then
-            echo "ZARR_TEST_ABS=0" >> "$GITHUB_ENV"
-        else
-            echo "ZARR_TEST_ABS=1" >> "$GITHUB_ENV"
+            PYTEST_ADDOPTS="-k 'not test_s3'"
         fi
         conda activate zarr-env
         mkdir ~/blob_emulator
diff --git a/.github/workflows/windows-testing.yml b/.github/workflows/windows-testing.yml
index 1e1f132c3c..6fb7648a2d 100644
--- a/.github/workflows/windows-testing.yml
+++ b/.github/workflows/windows-testing.yml
@@ -47,9 +47,7 @@ jobs:
         run: |
           # Skip ABS on 3.9, see https://github.com/zarr-developers/zarr-python/pull/1542/#issuecomment-1945557365 etc.
           if [[ "${{ matrix.python-version }}" == '3.9' ]]; then
-              echo "ZARR_TEST_ABS=0" >> "$GITHUB_ENV"
-          else
-              echo "ZARR_TEST_ABS=1" >> "$GITHUB_ENV"
+            PYTEST_ADDOPTS="-k 'not test_s3'"
           fi
           conda activate zarr-env
           mkdir ~/blob_emulator