Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 928 [Rate centres in NPA 928] [Dial plan for NPA 928]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
928-257 A Yuma AZ PHNDAZ91DS5  3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666      
928-257 0 Yuma AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2004-04-02   
928-257 1 Yuma AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666   2005-05-05   
928-257 2 Yuma AZ   6529 T-MOBILE USA, INC. 666   2004-04-26   
928-257 3 Yuma AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666   2005-01-26   
928-257 4 Yuma AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666      
928-257 5 Yuma AZ   6529 T-MOBILE USA, INC. 666   2004-03-26   
928-257 6 Yuma AZ   6529 T-MOBILE USA, INC. 666   2003-12-31   
928-257 7 Yuma AZ   6529 T-MOBILE USA, INC. 666   2005-02-03   
928-257 8 Yuma AZ   6529 T-MOBILE USA, INC. 666   2003-12-01   
928-257 9 Yuma AZ   5562 METROPCS, INC. 666   2003-11-17   

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

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