diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index 8f4da9620..753a35fcd 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -88,7 +88,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.9.18', '3.10.13', '3.11.5', '3.12.0']
+        # Note: py39, py310 versions chosen due to available arm64 darwin builds.
+        python-version: ['3.9.13', '3.10.11', '3.11.5', '3.12.0']
     runs-on: macos-latest
     steps:
       - uses: actions/checkout@v4