diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 4c63ffe159..223e2276cb 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -6150,7 +6150,7 @@ static int respprep(struct sip_request *resp, struct sip_pvt *p, const char *msg
 		add_header(resp, "Contact", p->our_contact);
 	}
 
-	if (p->url) {
+	if (!ast_strlen_zero(p->url)) {
 		add_header(resp, "Access-URL", p->url);
 		ast_string_field_free(p, url);
 	}
@@ -6260,7 +6260,7 @@ static int reqprep(struct sip_request *req, struct sip_pvt *p, int sipmethod, in
 	if (!ast_strlen_zero(p->rpid))
 		add_header(req, "Remote-Party-ID", p->rpid);
 
-	if (p->url) {
+	if (!ast_strlen_zero(p->url)) {
 		add_header(req, "Access-URL", p->url);
 		ast_string_field_free(p, url);
 	}