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.
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Switch: HYWRCA01DS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
510-247 A Hayward CA 9740 PACIFIC BELL 722      
510-537 A Hayward CA 9740 PACIFIC BELL 722      
510-538 A Hayward CA 9740 PACIFIC BELL 722      
510-581 A Hayward CA 9740 PACIFIC BELL 722      
510-582 A Hayward CA 9740 PACIFIC BELL 722      
510-583 A Hayward CA 9740 PACIFIC BELL 722      
510-690 A Hayward CA 9740 PACIFIC BELL 722      
510-727 A Hayward CA 9740 PACIFIC BELL 722      
510-728 A Hayward CA 9740 PACIFIC BELL 722      
510-733 A Hayward CA 9740 PACIFIC BELL 722      
510-881 A Hayward CA 9740 PACIFIC BELL 722      
510-885 A Hayward CA 9740 PACIFIC BELL 722      
510-886 A Hayward CA 9740 PACIFIC BELL 722      
510-888 A Hayward CA 9740 PACIFIC BELL 722      
510-889 A Hayward CA 9740 PACIFIC BELL 722      

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

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