Blocking an incoming number can either be done on the voice gateway running as an H.323 gateway or from the CUCM if the version is 7.1 or above. We will go over configuring this for an H.323 gateway. First you will need to create a translation rule to block out the specific number or numbers: voice translation-rule 10 rule 1 reject /4325554933/ Then we need to create a translation profile and add the rule to the profile: voice translation-profile call_block translated calling 10 We then need to add this profile to the incoming dial-peer which would normally be tied to port 0/0/0:23 when using a PRI. dial-peer voice 10 pots call-block translation-profile incoming call_block incoming called-number . direct-inward-dial port 0/0/0:23 To test this translation profile you can use this command: VoiceGateway#test voice translation-rule 10 4325554933 4325554933 blocked on rule 1