diff --git a/pkgs/development/python-modules/smart_open/default.nix b/pkgs/development/python-modules/smart_open/default.nix
index d5177dfd2e9..5486fb41952 100644
--- a/pkgs/development/python-modules/smart_open/default.nix
+++ b/pkgs/development/python-modules/smart_open/default.nix
@@ -13,12 +13,12 @@
 
 buildPythonPackage rec {
   pname = "smart_open";
-  version = "3.0.0";
+  version = "4.0.0";
   disabled = pythonOlder "3.5";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "7f4e85b71df5a3618f5447d0b417b7a3576308c839690a24a70338b8993684c3";
+    sha256 = "2ce157700821e285bbacd8d01ec7a4f2582765460e541f55b216cb135db8be24";
   };
 
   # nixpkgs version of moto is >=1.2.0, remove version pin to fix build