diff --git a/nixos/modules/virtualisation/google-compute-image.nix b/nixos/modules/virtualisation/google-compute-image.nix
index d41bb71f4cb..ff39f1bf8da 100644
--- a/nixos/modules/virtualisation/google-compute-image.nix
+++ b/nixos/modules/virtualisation/google-compute-image.nix
@@ -16,7 +16,7 @@ in
       PATH=$PATH:${pkgs.stdenv.lib.makeBinPath [ pkgs.gnutar pkgs.gzip ]}
       pushd $out
       mv $diskImage disk.raw
-      tar -Szcf nixos-image-${config.system.nixosLabel}-${pkgs.stdenv.system}.tar.gz disk.raw
+      tar -Szcf nixos-image-${config.system.nixosLabel}-${pkgs.stdenv.system}.raw.tar.gz disk.raw
       rm $out/disk.raw
       popd
     '';