Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 628 [Rate centres in NPA 628] [Dial plan for NPA 628]

NXX: 577

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
628-577 A Nicasio CA SNJUCACL7MD  965H FRACTEL, LLC 722      
628-577 2 Nicasio CA SNJUCACL2MD  197D VONAGE AMERICA LLC 722   2021-10-20   
628-577 4 Nicasio CA SNFCCA01XGX  516C AT&T CORP. 722   2025-01-08   
628-577 5 Nicasio CA SNFCCA21XNZ  624H ONVOY SPECTRUM, LLC 722   2021-11-08   
628-577 6 Nicasio CA SNFCCA21XNZ  624H ONVOY SPECTRUM, LLC 722   2021-11-08   
628-577 7 Nicasio CA SNJUCACL7MD  965H FRACTEL, LLC 722   2021-09-13   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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