Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 657 [Rate centres in NPA 657] [Dial plan for NPA 657]

NXX: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-331 A Anaheim CA LSANCARCD3S  649C ONVOY, LLC - CA 730      
657-331 0 Anaheim CA   6529 T-MOBILE USA, INC. 730   2016-08-08   
657-331 1 Anaheim CA   6529 T-MOBILE USA, INC. 730   2016-08-08   
657-331 2 Anaheim CA   6529 T-MOBILE USA, INC. 730   2025-12-13   
657-331 3 Anaheim CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2024-05-12   
657-331 4 Anaheim CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-09-05   
657-331 5 Anaheim CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-09-05   
657-331 6 Anaheim CA   649C ONVOY, LLC - CA 730   2017-09-21   
657-331 7 Anaheim CA   649C ONVOY, LLC - CA 730   2017-09-21   
657-331 8 Anaheim CA   649C ONVOY, LLC - CA 730   2017-09-21   
657-331 9 Anaheim CA   649C ONVOY, LLC - CA 730   2017-09-21   

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

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