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: 377

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-377 A Garden Grove CA LSANCARCD3S  649C ONVOY, LLC - CA 730      
657-377 0 Garden Grove CA   649C ONVOY, LLC - CA 730   2016-05-20   
657-377 1 Garden Grove CA   649C ONVOY, LLC - CA 730   2016-05-20   
657-377 2 Garden Grove CA   649C ONVOY, LLC - CA 730   2016-05-21   
657-377 3 Garden Grove CA   649C ONVOY, LLC - CA 730   2016-05-21   
657-377 4 Garden Grove CA   516C AT&T CORP. 730   2016-10-09   
657-377 5 Garden Grove CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2019-03-02   
657-377 6 Garden Grove CA   6529 T-MOBILE USA, INC. 730   2016-07-23   
657-377 7 Garden Grove CA   6529 T-MOBILE USA, INC. 730   2016-07-23   
657-377 8 Garden Grove CA   6529 T-MOBILE USA, INC. 730   2016-05-21   
657-377 9 Garden Grove CA   6529 T-MOBILE USA, INC. 730   2016-05-21   

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

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