diff --git a/pkgs/by-name/sp/spass/package.nix b/pkgs/by-name/sp/spass/package.nix
index b629b8efe518..945a4a12fc41 100644
--- a/pkgs/by-name/sp/spass/package.nix
+++ b/pkgs/by-name/sp/spass/package.nix
@@ -20,7 +20,7 @@ gccStdenv.mkDerivation {
   version = "${baseVersion}.${minorVersion}";
 
   src = fetchurl {
-    url = "http://www.spass-prover.org/download/sources/spass${baseVersion}${minorVersion}.tgz";
+    url = "https://www.spass-prover.org/download/sources/spass${baseVersion}${minorVersion}.tgz";
     sha256 = "11cyn3kcff4r79rsw2s0xm6rdb8bi0kpkazv2b48jhcms7xw75qp";
   };