diff --git a/pkgs/development/python-modules/python-crontab/default.nix b/pkgs/development/python-modules/python-crontab/default.nix
index 0cbb5666bb05..8af332aa316b 100644
--- a/pkgs/development/python-modules/python-crontab/default.nix
+++ b/pkgs/development/python-modules/python-crontab/default.nix
@@ -37,6 +37,7 @@ buildPythonPackage rec {
     "test_03_usage"
     # Test is assuming $CURRENT_YEAR is not a leap year
     "test_19_frequency_at_month"
+    "test_20_frequency_at_year"
   ];
 
   pythonImportsCheck = [