diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 0f1f35b5a1..d6ed5633ae 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -11145,7 +11145,7 @@ static int handle_request(struct sip_pvt *p, struct sip_request *req, struct soc
 		/* Make sure we don't ignore this */
 		if (seqno == p->pendinginvite) {
 			p->pendinginvite = 0;
-			__sip_ack(p, seqno, FLAG_RESPONSE, -1);
+			__sip_ack(p, seqno, FLAG_RESPONSE, 0);
 			if (!ast_strlen_zero(get_header(req, "Content-Type"))) {
 				if (process_sdp(p, req))
 					return -1;