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: 275

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-275 A Placentia CA   6529 T-MOBILE USA, INC. 730      
657-275 0 Placentia CA   515J IP HORIZON LLC 730   2015-10-31   
657-275 1 Placentia CA   649C ONVOY, LLC - CA 730   2016-02-26   
657-275 2 Placentia CA   6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2015-09-25   
657-275 3 Placentia CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2016-07-29   
657-275 4 Placentia CA   6529 T-MOBILE USA, INC. 730   2016-12-08   
657-275 5 Placentia CA   6529 T-MOBILE USA, INC. 730   2016-12-08   
657-275 7 Placentia CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2025-07-12   
657-275 8 Placentia CA   649C ONVOY, LLC - CA 730   2016-02-26   
657-275 9 Placentia CA   576C TIME WARNER CBL INFO SVCS (CA) DBA TIME WARNER CAB 730   2015-08-31   

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

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