diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3f86f69e38..a5d3d9f813 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -37,6 +37,7 @@
 * [BUGFIX] Compactor: Fix stale `cortex_bucket_index_last_successful_update_timestamp_seconds` metric not being cleaned up when tenant ownership changes due to ring rebalancing. This caused false alarms on bucket index update rate when a tenant moved between compactors. #7485
 * [BUGFIX] Security: Fix stored XSS vulnerability in Alertmanager and Store Gateway status pages by replacing `text/template` with `html/template`. #7512
 * [BUGFIX] Security: Limit decompressed gzip output in `ParseProtoReader` and OTLP ingestion path. The decompressed body is now capped by `-distributor.otlp-max-recv-msg-size`. #7515
+* [BUGFIX] Compactor: Wait for the blocks cleaner `VisitMarkerManager.HeartBeat` goroutine to exit before returning from per-user cleanup callbacks, preventing a late `MarkWithStatus(Completed)` and `DeleteVisitMarker` write from racing with test teardown and causing `unlinkat: directory not empty` flakes in `TestBlocksCleaner`. #7564
 
 ## 1.21.0 2026-04-24
 
diff --git a/pkg/compactor/blocks_cleaner.go b/pkg/compactor/blocks_cleaner.go
index e7633c9d67..508a34432e 100644
--- a/pkg/compactor/blocks_cleaner.go
+++ b/pkg/compactor/blocks_cleaner.go
@@ -357,9 +357,15 @@ func (c *BlocksCleaner) cleanUpActiveUsers(ctx context.Context, users []string,
 			return nil
 		}
 		errChan := make(chan error, 1)
-		go visitMarkerManager.HeartBeat(ctx, errChan, c.cleanerVisitMarkerFileUpdateInterval, true)
+		var hbWG sync.WaitGroup
+		hbWG.Add(1)
+		go func() {
+			defer hbWG.Done()
+			visitMarkerManager.HeartBeat(ctx, errChan, c.cleanerVisitMarkerFileUpdateInterval, true)
+		}()
 		defer func() {
 			errChan <- nil
+			hbWG.Wait()
 		}()
 		return errors.Wrapf(c.cleanUser(ctx, userLogger, userBucket, userID, firstRun), "failed to delete blocks for user: %s", userID)
 	})
@@ -392,9 +398,15 @@ func (c *BlocksCleaner) cleanDeletedUsers(ctx context.Context, users []string) e
 			return nil
 		}
 		errChan := make(chan error, 1)
-		go visitMarkerManager.HeartBeat(ctx, errChan, c.cleanerVisitMarkerFileUpdateInterval, true)
+		var hbWG sync.WaitGroup
+		hbWG.Add(1)
+		go func() {
+			defer hbWG.Done()
+			visitMarkerManager.HeartBeat(ctx, errChan, c.cleanerVisitMarkerFileUpdateInterval, true)
+		}()
 		defer func() {
 			errChan <- nil
+			hbWG.Wait()
 		}()
 		return errors.Wrapf(c.deleteUserMarkedForDeletion(ctx, userLogger, userBucket, userID), "failed to delete user marked for deletion: %s", userID)
 	})