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: 455

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-455 A Phoenix AZ PHNDAZ91DS5  3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666      
623-455 0 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2006-05-01   
623-455 1 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2006-05-01   
623-455 2 Phoenix AZ   6529 T-MOBILE USA, INC. 666   2006-05-01   
623-455 3 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2006-06-05   
623-455 4 Phoenix AZ   2191 ACCIPITER COMMUNICATIONS INC 666   2006-05-07   
623-455 5 Phoenix AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666   2005-02-21   
623-455 6 Phoenix AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666   2005-02-21   
623-455 7 Phoenix AZ   9636 QWEST CORPORATION 666   2006-04-17   
623-455 8 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2006-06-05   
623-455 9 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2006-06-05   

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

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