diff --git a/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp b/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp
index efc1072e76..90972f37ec 100644
--- a/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp
+++ b/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp
@@ -577,6 +577,8 @@ BPlusTree::~BPlusTree()
 		iterator.Next()->Stop();
 
 	mutex_destroy(&fIteratorLock);
+
+	ASSERT(!fInTransaction);
 }