diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index aadd0998999d..493b1d96a684 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -27642,12 +27642,12 @@ in modules // {
 
   IMAPClient = buildPythonPackage rec {
     name = "IMAPClient-${version}";
-    version = "0.11";
+    version = "0.13";
     disabled = isPy34 || isPy35;
 
     src = pkgs.fetchurl {
       url = "http://freshfoo.com/projects/IMAPClient/${name}.tar.gz";
-      sha256 = "1w54h8gz25qf6ggazzp6xf7kvsyiadsjfkkk17gm0p6pmzvvccbn";
+      sha256 = "0v7kd1crdbff0rmh4ddm5qszkis6hpk9084qh94al8h7g4y9l3is";
     };
 
     buildInputs = with self; [ mock ];