diff --git a/.github/workflows/close_stale_prs.yml b/.github/workflows/close_stale_prs.yml
index 8ff44179d74..d34b44d55ca 100644
--- a/.github/workflows/close_stale_prs.yml
+++ b/.github/workflows/close_stale_prs.yml
@@ -2,6 +2,7 @@
 name: Close stale PRs
 
 on:
+  pull_request:
   schedule:
     # Every day at 1:39 AM UTC. A random time to avoid GitHub Actions being overloaded by scheduled workflows.
     - cron: '39 1 * * *'