diff --git a/pkgs/applications/networking/mailreaders/notmuch/default.nix b/pkgs/applications/networking/mailreaders/notmuch/default.nix
index a8502b33cc5..212d366facb 100644
--- a/pkgs/applications/networking/mailreaders/notmuch/default.nix
+++ b/pkgs/applications/networking/mailreaders/notmuch/default.nix
@@ -95,6 +95,7 @@ stdenv.mkDerivation rec {
   postInstall = ''
     make install-man
   '';
+  dontGzipMan = true; # already compressed
 
   meta = {
     description = "Mail indexer";