Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 303 [Rate centres in NPA 303] [Dial plan for NPA 303]

NXX: 856

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
303-856 A Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-856 0 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-856 1 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-856 2 Denver CO DNVTCO56DS8  6118 LEVEL 3 COMMUNICATIONS, LLC - CO 656      
303-856 3 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2007-03-09   
303-856 4 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656   2009-07-29   
303-856 5 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656   2009-07-29   
303-856 6 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656   2009-07-29   
303-856 7 Denver CO DNVRCOMA39Z  318J COMCAST IP PHONE, LLC 656   2007-03-09   
303-856 8 Denver CO DNVRCOII3MD  6529 T-MOBILE USA, INC. 656   2006-02-09   
303-856 9 Denver CO DNVTCOZIDS1  026D ONVOY, LLC - CO 656   2021-08-25   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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