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: 608

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-608 A Fremont-Newark: Main DA CA FRMTCA11DS0  9740 PACIFIC BELL 722      
510-608 0 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 1 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 2 Fremont-Newark: Main DA CA   649C ONVOY, LLC - CA 722   2022-12-15   
510-608 3 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 4 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 5 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 6 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 7 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 8 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      
510-608 9 Fremont-Newark: Main DA CA   9740 PACIFIC BELL 722      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: Execulink Telecom

Like this site? We accept donations via PayPal.