Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 510 [Rate centres in NPA 510] [Dial plan for NPA 510]

NXX: 994

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-994 A Richmond CA SNFCCA21XUY  981E BANDWIDTH.COM CLEC, LLC - CA 722      
510-994 0 Richmond CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2019-09-23   
510-994 1 Richmond CA   6529 T-MOBILE USA, INC. 722   2020-08-05   
510-994 2 Richmond CA   981E BANDWIDTH.COM CLEC, LLC - CA 722   2021-01-23   
510-994 3 Richmond CA   624H ONVOY SPECTRUM, LLC 722   2021-03-02   
510-994 4 Richmond CA   197D VONAGE AMERICA LLC 722   2020-06-15   
510-994 5 Richmond CA   197D VONAGE AMERICA LLC 722   2020-06-15   
510-994 6 Richmond CA   6529 T-MOBILE USA, INC. 722   2020-01-20   
510-994 7 Richmond CA   6529 T-MOBILE USA, INC. 722   2020-01-20   
510-994 8 Richmond CA   6529 T-MOBILE USA, INC. 722   2019-10-22   
510-994 9 Richmond CA   6529 T-MOBILE USA, INC. 722   2019-10-22   

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

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.