diff --git a/src/plugins/lazy-expunge/lazy-expunge-plugin.c b/src/plugins/lazy-expunge/lazy-expunge-plugin.c
index 8a357d79ce..89491d71a4 100644
--- a/src/plugins/lazy-expunge/lazy-expunge-plugin.c
+++ b/src/plugins/lazy-expunge/lazy-expunge-plugin.c
@@ -109,7 +109,8 @@ mailbox_open_or_create(struct mailbox_list *list, struct mailbox *src_box,
 
 	name = get_dest_vname(list, src_box);
 
-	box = mailbox_alloc(list, name, MAILBOX_FLAG_NO_INDEX_FILES);
+	box = mailbox_alloc(list, name, MAILBOX_FLAG_NO_INDEX_FILES |
+			    MAILBOX_FLAG_SAVEONLY);
 	if (mailbox_open(box) == 0) {
 		*error_r = NULL;
 		return box;