diff --git a/.github/workflows/run-tests.yml b/.github/workflows/run-tests.yml
index 0b7dc997be..8637203783 100644
--- a/.github/workflows/run-tests.yml
+++ b/.github/workflows/run-tests.yml
@@ -21,13 +21,13 @@ jobs:
       fail-fast: false
       matrix:
         python-version: ["3.7", "3.8", "3.9", "3.10", "3.11", "3.12", "3.13", "pypy-3.9", "pypy-3.10"]
-        os: [ubuntu-latest, macOS-13, windows-latest]
+        os: [ubuntu-22.04, macOS-13, windows-latest]
         include:
           # pypy-3.7, pypy-3.8 may fail due to missing cryptography wheels. Adapting.
           - python-version: pypy-3.7
-            os: ubuntu-latest
+            os: ubuntu-22.04
           - python-version: pypy-3.8
-            os: ubuntu-latest
+            os: ubuntu-22.04
           - python-version: pypy-3.8
             os: macOS-13