diff --git a/lib/api/gitlab.js b/lib/api/gitlab.js
index 2a27bac6d02e985eb82bdb6bada88e5a560a9d9a..ce1004c87037e34c2a2451b6ec95edca731d06fc 100644
--- a/lib/api/gitlab.js
+++ b/lib/api/gitlab.js
@@ -134,7 +134,7 @@ async function getBranchPr(branchName) {
   if (!pr) {
     return null;
   }
-  return getPr(pr.id);
+  return getPr(config.apiVersion === 'v3' ? pr.id : pr.iid);
 }
 
 // Returns the combined status for a branch.