Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 510 [Rate centres in NPA 510] [Dial plan for NPA 510]

NXX: 374

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-374 A Richmond CA RCMDCA11RS2  9740 PACIFIC BELL 722      
510-374 0 Richmond CA   6010 NEW CINGULAR WIRELESS PCS, LLC 722   2006-07-06   
510-374 1 Richmond CA   9740 PACIFIC BELL 722      
510-374 2 Richmond CA   6529 T-MOBILE USA, INC. 722   2006-06-05   
510-374 3 Richmond CA   9740 PACIFIC BELL 722      
510-374 4 Richmond CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 722   2006-07-14   
510-374 5 Richmond CA   9262 UTILITY TELECOM GROUP, LLC - CA 722   2006-05-15   
510-374 6 Richmond CA   516C AT&T CORP. 722   2006-06-30   
510-374 7 Richmond CA   9740 PACIFIC BELL 722      
510-374 8 Richmond CA   6010 NEW CINGULAR WIRELESS PCS, LLC 722   2006-07-21   
510-374 9 Richmond CA   6010 NEW CINGULAR WIRELESS PCS, LLC 722   2006-07-06   

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

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