diff --git a/pkgs/development/python-modules/mailchecker/default.nix b/pkgs/development/python-modules/mailchecker/default.nix
index 6e1958f56995..107b8dcb82da 100644
--- a/pkgs/development/python-modules/mailchecker/default.nix
+++ b/pkgs/development/python-modules/mailchecker/default.nix
@@ -6,14 +6,14 @@
 
 buildPythonPackage rec {
   pname = "mailchecker";
-  version = "5.0.3";
+  version = "5.0.4";
   format = "setuptools";
 
   disabled = pythonOlder "3.7";
 
   src = fetchPypi {
     inherit pname version;
-    hash = "sha256-D8xyXBUDRaXLempcJ7G/Ybe7A3FiAaZ8kgm4jgKhkSI=";
+    hash = "sha256-CTeZ63hOBUHuuIJgWRNttBRgrHSsuL78zo6MW8VwEDE=";
   };
 
   # Module has no tests