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: 550

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
928-550 A Somerton AZ TEMPAZNR5MD  6529 T-MOBILE USA, INC. 666      
928-550 0 Somerton AZ   6529 T-MOBILE USA, INC. 666   2005-07-24   
928-550 1 Somerton AZ   6529 T-MOBILE USA, INC. 666   2006-05-01   
928-550 2 Somerton AZ   6529 T-MOBILE USA, INC. 666   2006-08-21   
928-550 3 Somerton AZ   6529 T-MOBILE USA, INC. 666   2006-08-21   
928-550 4 Somerton AZ   3285 LEVEL 3 COMMUNICATIONS, LLC - AZ 666   2005-08-28   
928-550 5 Somerton AZ   793K TWC IP ENABLED SERVICES, LLC 666   2006-11-28   
928-550 6 Somerton AZ   630E ONVOY, LLC - AZ 666   2012-05-18   
928-550 7 Somerton AZ   630E ONVOY, LLC - AZ 666   2007-05-25   
928-550 8 Somerton AZ   6529 T-MOBILE USA, INC. 666   2007-02-08   
928-550 9 Somerton AZ   6529 T-MOBILE USA, INC. 666   2005-07-24   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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