diff --git a/include/event2/bufferevent.h b/include/event2/bufferevent.h
index 467b4e32..9e65873f 100644
--- a/include/event2/bufferevent.h
+++ b/include/event2/bufferevent.h
@@ -277,6 +277,9 @@ int bufferevent_priority_set(struct bufferevent *bufev, int pri);
 /**
   Deallocate the storage associated with a bufferevent structure.
 
+  If there is pending data to write on the bufferevent, it probably won't be
+  flushed before the bufferevent is freed.
+
   @param bufev the bufferevent structure to be freed.
   */
 void bufferevent_free(struct bufferevent *bufev);