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.

Switch: MLPTCAVPAMD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
341-255 A Oakland: Berkeley DA CA 0051 SHELCOMM 722   2024-11-01   
369-220 A Sonoma CA 0051 SHELCOMM 722   2024-11-03   
369-221 A Santa Rosa CA 0051 SHELCOMM 722   2024-11-03   
510-510 A Fremont-Newark: Main DA CA 0051 SHELCOMM 722   2024-11-03   
628-314 A San Rafael CA 0051 SHELCOMM 722   2024-11-03   
650-221 A South San Francisco CA 0051 SHELCOMM 722   2024-11-03   
669-355 A San Jose: North DA CA 0051 SHELCOMM 722   2024-11-03   
669-357 A Sunnyvale CA 0051 SHELCOMM 722   2024-11-03   
831-314 A Santa Cruz CA 0051 SHELCOMM 722   2024-11-03   
925-541 A Livermore CA 0051 SHELCOMM 722   2024-11-03   

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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