diff --git a/pkgs/build-support/fetchbitbucket/default.nix b/pkgs/build-support/fetchbitbucket/default.nix
index b98fc21de7ba..b5f04d8afbd1 100644
--- a/pkgs/build-support/fetchbitbucket/default.nix
+++ b/pkgs/build-support/fetchbitbucket/default.nix
@@ -15,7 +15,7 @@ lib.makeOverridable (
   fetchzip (
     {
       inherit name;
-      url = "https://bitbucket.org/${owner}/${repo}/get/${rev}.tar.gz";
+      url = "https://bitbucket.org/${owner}/${repo}/get/${lib.strings.escapeURL rev}.tar.gz";
       meta.homepage = "https://bitbucket.org/${owner}/${repo}/";
     }
     // removeAttrs args [
diff --git a/pkgs/build-support/fetchbitbucket/tests.nix b/pkgs/build-support/fetchbitbucket/tests.nix
new file mode 100644
index 000000000000..4e9b97b7e709
--- /dev/null
+++ b/pkgs/build-support/fetchbitbucket/tests.nix
@@ -0,0 +1,18 @@
+{ testers, fetchFromBitbucket, ... }:
+{
+  withEncodedWhitespace = testers.invalidateFetcherByDrvHash fetchFromBitbucket {
+    name = "withWhitespace";
+    owner = "tetov";
+    repo = "fetchbitbucket_tester";
+    rev = "tag%20with%20encoded%20spaces";
+    sha256 = "sha256-Nf1Cvbx7Sbab8EeSSBU5baLBiuFYiQtITED+f4tfjC0=";
+  };
+
+  withoutWhitespace = testers.invalidateFetcherByDrvHash fetchFromBitbucket {
+    name = "withoutWhitespace";
+    owner = "tetov";
+    repo = "fetchbitbucket_tester";
+    rev = "main";
+    sha256 = "sha256-eTd773gE1z4+Fl2YPBbbsrADD4Dr7sFGoOWgphXUhtE=";
+  };
+}
diff --git a/pkgs/test/default.nix b/pkgs/test/default.nix
index fe6f9eb43852..6314049ed0bc 100644
--- a/pkgs/test/default.nix
+++ b/pkgs/test/default.nix
@@ -131,6 +131,7 @@ with pkgs;
   fetchDebianPatch = recurseIntoAttrs (callPackages ../build-support/fetchdebianpatch/tests.nix { });
   fetchzip = recurseIntoAttrs (callPackages ../build-support/fetchzip/tests.nix { });
   fetchgit = recurseIntoAttrs (callPackages ../build-support/fetchgit/tests.nix { });
+  fetchFromBitbucket = recurseIntoAttrs (callPackages ../build-support/fetchbitbucket/tests.nix { });
   fetchFirefoxAddon = recurseIntoAttrs (
     callPackages ../build-support/fetchfirefoxaddon/tests.nix { }
   );