diff --git a/.github/workflows/_rust.yml b/.github/workflows/_rust.yml
index 4ca8ac9c2..c7558f0e6 100644
--- a/.github/workflows/_rust.yml
+++ b/.github/workflows/_rust.yml
@@ -116,6 +116,7 @@ jobs:
           # Needed to create tunnel interfaces in unit tests
           CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_RUNNER: "sudo --preserve-env"
           PROPTEST_VERBOSE: 0 # Otherwise the output is very long.
+          PROPTEST_CASES: ${{ runner.os == 'Windows' && '0' || '256' }} # Default is only 256. Windows is very slow in GitHub Actions, so only run the regression cases there.
           CARGO_PROFILE_TEST_OPT_LEVEL: 1 # Otherwise the tests take forever.
           TESTCASES_DIR: "connlib/tunnel/testcases"