diff --git a/lib/platform/github/index.js b/lib/platform/github/index.js
index <HASH>..<HASH> 100644
--- a/lib/platform/github/index.js
+++ b/lib/platform/github/index.js
@@ -849,7 +849,13 @@ async function ensureComment(issueNo, topic, content) {
     }
     return true;
   } catch (err) /* istanbul ignore next */ {
-    logger.warn({ err }, 'Error ensuring comment');
+    if (
+      err.message === 'Unable to create comment because issue is locked. (403)'
+    ) {
+      logger.info('Issue is locked - cannot add comment');
+    } else {
+      logger.warn({ err }, 'Error ensuring comment');
+    }
     return false;
   }
 }
@@ -868,7 +874,13 @@ async function ensureCommentRemoval(issueNo, topic) {
       await deleteComment(commentId);
     }
   } catch (err) /* istanbul ignore next */ {
-    logger.warn({ err }, 'Error ensuring comment removal');
+    if (
+      err.message === 'Unable to create comment because issue is locked. (403)'
+    ) {
+      logger.info('Issue is locked - cannot add comment');
+    } else {
+      logger.warn({ err }, 'Error ensuring comment removal');
+    }
   }
 }
refactor(github): don’t warn if failing to comment on locked issue