Local Calling Guide

Area code/prefix search

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NPA: 657 [Rate centres in NPA 657] [Dial plan for NPA 657]

NXX: 751

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-751 A Fullerton CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2024-07-13   
657-751 0 Fullerton CA LSANCA03GMD  624H ONVOY SPECTRUM, LLC 730   2024-11-01   
657-751 1 Fullerton CA LSANCA03GMD  624H ONVOY SPECTRUM, LLC 730   2024-11-01   
657-751 2 Fullerton CA LSANCA03GMD  624H ONVOY SPECTRUM, LLC 730   2024-11-01   
657-751 3 Fullerton CA LSANCA03GMD  624H ONVOY SPECTRUM, LLC 730   2024-11-01   
657-751 4 Fullerton CA LSANCA03GMD  624H ONVOY SPECTRUM, LLC 730   2024-11-01   
657-751 6 Fullerton CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2024-11-18   
657-751 7 Fullerton CA CYCMCALLCM5  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2024-09-09   
657-751 8 Fullerton CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2024-07-13   
657-751 9 Fullerton CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2024-07-13   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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