diff --git a/lib/platform/github/index.ts b/lib/platform/github/index.ts
index e99496f987b82f541559c8dbdd563c1bc237ede5..3d1e932740d3a18d5f06ccd949e5c1d8aa0a3e40 100644
--- a/lib/platform/github/index.ts
+++ b/lib/platform/github/index.ts
@@ -1569,9 +1569,13 @@ export async function mergePr(
   const url = `repos/${
     config.parentRepo || config.repository
   }/pulls/${prNo}/merge`;
-  const options = {
+  const options: any = {
     body: {} as { merge_method?: string },
   };
+  // istanbul ignore if
+  if (config.forkToken) {
+    options.token = config.forkToken;
+  }
   let automerged = false;
   if (config.mergeMethod) {
     // This path is taken if we have auto-detected the allowed merge types from the repo
@@ -1588,7 +1592,7 @@ export async function mergePr(
           'GitHub blocking PR merge -- will keep trying'
         );
       } else {
-        logger.warn({ err }, `Failed to ${options.body.merge_method} merge PR`);
+        logger.warn({ err }, `Failed to ${config.mergeMethod} merge PR`);
         return false;
       }
     }
@@ -1600,29 +1604,20 @@ export async function mergePr(
       logger.debug({ options, url }, `mergePr`);
       await githubApi.putJson(url, options);
     } catch (err1) {
-      logger.debug(
-        { err: err1 },
-        `Failed to ${options.body.merge_method} merge PR`
-      );
+      logger.debug({ err: err1 }, `Failed to rebase merge PR`);
       try {
         options.body.merge_method = 'squash';
         logger.debug({ options, url }, `mergePr`);
         await githubApi.putJson(url, options);
       } catch (err2) {
-        logger.debug(
-          { err: err2 },
-          `Failed to ${options.body.merge_method} merge PR`
-        );
+        logger.debug({ err: err2 }, `Failed to merge squash PR`);
         try {
           options.body.merge_method = 'merge';
           logger.debug({ options, url }, `mergePr`);
           await githubApi.putJson(url, options);
         } catch (err3) {
-          logger.debug(
-            { err: err3 },
-            `Failed to ${options.body.merge_method} merge PR`
-          );
-          logger.debug({ pr: prNo }, 'All merge attempts failed');
+          logger.debug({ err: err3 }, `Failed to merge commit PR`);
+          logger.info({ pr: prNo }, 'All merge attempts failed');
           return false;
         }
       }