diff --git a/lib/evaluate.py b/lib/evaluate.py
index 8251bbd..2595137 100644
--- a/lib/evaluate.py
+++ b/lib/evaluate.py
@@ -533,6 +533,7 @@ async def evaluate_pr(conn, pr_number: int, tier: str = None) -> dict:
     diff = await get_pr_diff(pr_number)
     if not diff:
         # Close PRs with no diff — stale branch, nothing to evaluate
+        await forgejo_api("PATCH", repo_path(f"pulls/{pr_number}"), {"state": "closed"})
         conn.execute("UPDATE prs SET status='closed', last_error='closed: no diff against main (stale branch)' WHERE number = ?", (pr_number,))
         return {"pr": pr_number, "skipped": True, "reason": "no_diff_closed"}
 
diff --git a/lib/merge.py b/lib/merge.py
index a84e109..c1f3ca1 100644
--- a/lib/merge.py
+++ b/lib/merge.py
@@ -1771,6 +1771,7 @@ async def _handle_permanent_conflicts(conn) -> int:
             except Exception:
                 pass
 
+        await forgejo_api("PATCH", repo_path(f"pulls/{pr_number}"), {"state": "closed"})
         conn.execute(
             "UPDATE prs SET status = 'closed', last_error = 'conflict_permanent: closed + filed in archive' WHERE number = ?",
             (pr_number,),