Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 623 [Rate centres in NPA 623] [Dial plan for NPA 623]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-666 A Phoenix AZ PHNXAZ28DS3  630E ONVOY, LLC - AZ 666      
623-666 0 Phoenix AZ   5562 METROPCS, INC. 666   2014-07-16   
623-666 1 Phoenix AZ   5562 METROPCS, INC. 666   2014-07-16   
623-666 2 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2014-04-04   
623-666 3 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2014-04-04   
623-666 4 Phoenix AZ   630E ONVOY, LLC - AZ 666   2013-01-10   
623-666 5 Phoenix AZ   630E ONVOY, LLC - AZ 666   2013-01-10   
623-666 6 Phoenix AZ   630E ONVOY, LLC - AZ 666   2013-01-10   
623-666 7 Phoenix AZ   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 666   2013-08-10   
623-666 8 Phoenix AZ   630E ONVOY, LLC - AZ 666   2013-11-01   
623-666 9 Phoenix AZ   630E ONVOY, LLC - AZ 666   2013-11-01   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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