diff --git a/lib/platform/github/index.js b/lib/platform/github/index.js
index a3840cb219dc6ee5703486843fa8facc0fb4942e..4502e70b86332c564f28ef231d74a6d841f3cab3 100644
--- a/lib/platform/github/index.js
+++ b/lib/platform/github/index.js
@@ -485,6 +485,11 @@ async function setBranchStatus(
   state,
   targetUrl
 ) {
+  // istanbul ignore if
+  if (config.parentRepo) {
+    logger.info('Cannot set branch status when in forking mode');
+    return;
+  }
   const existingStatus = await getBranchStatusCheck(branchName, context);
   if (existingStatus === state) {
     return;