diff --git a/lib/message.cc b/lib/message.cc
index 75f36bdd..63d67cfe 100644
--- a/lib/message.cc
+++ b/lib/message.cc
@@ -1560,6 +1560,13 @@ _ensure_maildir_flags (notmuch_message_t *message, notmuch_bool_t force)
 	message->maildir_flags = combined_flags;
 }
 
+notmuch_bool_t
+notmuch_message_has_maildir_flag (notmuch_message_t *message, char flag)
+{
+    _ensure_maildir_flags (message, FALSE);
+    return message->maildir_flags && (strchr (message->maildir_flags, flag) != NULL);
+}
+
 notmuch_status_t
 notmuch_message_maildir_flags_to_tags (notmuch_message_t *message)
 {
diff --git a/lib/notmuch.h b/lib/notmuch.h
index e025bc1f..66ecb5fc 100644
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -1612,6 +1612,14 @@ notmuch_message_remove_all_tags (notmuch_message_t *message);
 notmuch_status_t
 notmuch_message_maildir_flags_to_tags (notmuch_message_t *message);
 
+/**
+ * return TRUE if any filename of 'message' has maildir flag 'flag',
+ * FALSE otherwise.
+ *
+ */
+notmuch_bool_t
+notmuch_message_has_maildir_flag (notmuch_message_t *message, char flag);
+
 /**
  * Rename message filename(s) to encode tags as maildir flags.
  *