diff --git a/plugins/sierra.c b/plugins/sierra.c
index c41e2d13..b33382d0 100644
--- a/plugins/sierra.c
+++ b/plugins/sierra.c
@@ -79,6 +79,9 @@ static void sierra_remove(struct ofono_modem *modem)
 
 	ofono_modem_set_data(modem, NULL);
 
+	/* Cleanup after hot-unplug */
+	g_at_chat_unref(data->chat);
+
 	g_free(data);
 }