diff --git a/app/dialplans/resources/switch/conf/dialplan/345_nb-conference.xml b/app/dialplans/resources/switch/conf/dialplan/345_nb-conference.xml
index 3d02c7ee2f..585efc4808 100644
--- a/app/dialplans/resources/switch/conf/dialplan/345_nb-conference.xml
+++ b/app/dialplans/resources/switch/conf/dialplan/345_nb-conference.xml
@@ -1,6 +1,6 @@
 <!-- Used to transfer both legs into a conference -->
 <extension name="nb-conference" context="global" continue="false" app_uuid="be99ad65-dcf0-40dd-8bf6-0640c52befcd" global="true" order="345">
-	<condition field="destination_number" expression="^\*(30(.*))$">
+	<condition field="destination_number" expression="^\*30(\d{2,7})$">
 		<action application="conference" data="$1@${context}@default"/>
 	</condition>
 </extension>