diff --git a/.github/workflows/pr-title.yml b/.github/workflows/pr-title.yml
index 80d75b0c30..dc404a1441 100644
--- a/.github/workflows/pr-title.yml
+++ b/.github/workflows/pr-title.yml
@@ -36,7 +36,7 @@ jobs:
         with:
           # pull_request_target checks out the base branch by default, not
           # the PR branch.
-          ref: "${{ github.event.pull_request.merge_commit_sha }}"
+          ref: "${{ github.event.pull_request.head.sha }}"
           path: pr
       - uses: actions/setup-python@v5
         with: