diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 80d7151c02..44f9e0f742 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -16887,9 +16887,8 @@ static enum check_auth_result register_verify(struct sip_pvt *p, struct ast_sock
 		} else {
 
 			set_peer_nat(p, peer);
-			if (p->natdetected && ast_test_flag(&p->flags[2], SIP_PAGE3_NAT_AUTO_RPORT)) {
-				ast_copy_flags(&p->flags[0], &peer->flags[0], SIP_NAT_FORCE_RPORT);
-			}
+
+			ast_copy_flags(&p->flags[0], &peer->flags[0], SIP_NAT_FORCE_RPORT);
 
 			if (!(res = check_auth(p, req, peer->name, peer->secret, peer->md5secret, SIP_REGISTER, uri2, XMIT_UNRELIABLE))) {
 				if (sip_cancel_destroy(p))