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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
928-421 A Winslow AZ PHNXAZMAXQX  587F BANDWIDTH.COM CLEC, LLC - AZ 666      
928-421 0 Winslow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2014-04-27   
928-421 1 Winslow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2014-04-27   
928-421 2 Winslow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2015-02-19   
928-421 3 Winslow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2015-02-19   
928-421 4 Winslow AZ   587F BANDWIDTH.COM CLEC, LLC - AZ 666   2015-02-19   
928-421 6 Winslow AZ   5562 METROPCS, INC. 666   2016-06-17   
928-421 7 Winslow AZ   508J CENTURYLINK COMMUNICATIONS, LLC 666   2015-09-26   
928-421 8 Winslow AZ   630E ONVOY, LLC - AZ 666   2016-03-14   
928-421 9 Winslow AZ   6010 NEW CINGULAR WIRELESS PCS, LLC 666   2015-11-19   

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

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