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: BRLNCA01DS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
650-340 A San Mateo CA 9740 PACIFIC BELL 722      
650-342 A San Mateo CA 9740 PACIFIC BELL 722      
650-343 A San Mateo CA 9740 PACIFIC BELL 722      
650-344 A San Mateo CA 9740 PACIFIC BELL 722      
650-347 A San Mateo CA 9740 PACIFIC BELL 722      
650-348 A San Mateo CA 9740 PACIFIC BELL 722      
650-373 A San Mateo CA 9740 PACIFIC BELL 722      
650-375 A San Mateo CA 9740 PACIFIC BELL 722      
650-401 A San Mateo CA 9740 PACIFIC BELL 722      
650-548 A San Mateo CA 9740 PACIFIC BELL 722      
650-558 A San Mateo CA 9740 PACIFIC BELL 722      
650-579 A San Mateo CA 9740 PACIFIC BELL 722      
650-612 A San Mateo CA 9740 PACIFIC BELL 722      
650-685 A San Mateo CA 9740 PACIFIC BELL 722      
650-696 A San Mateo CA 9740 PACIFIC BELL 722      
650-762 A San Mateo CA 9740 PACIFIC BELL 722      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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