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: SNMTCA11DS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
650-212 A San Mateo CA 9740 PACIFIC BELL 722      
650-286 A San Mateo CA 9740 PACIFIC BELL 722      
650-287 A San Mateo CA 9740 PACIFIC BELL 722      
650-293 A San Mateo CA 9740 PACIFIC BELL 722      
650-294 A San Mateo CA 9740 PACIFIC BELL 722      
650-295 A San Mateo CA 9740 PACIFIC BELL 722      
650-312 A San Mateo CA 9740 PACIFIC BELL 722      
650-350 A San Mateo CA 9740 PACIFIC BELL 722      
650-432 A San Mateo CA 9740 PACIFIC BELL 722      
650-513 A San Mateo CA 9740 PACIFIC BELL 722      
650-525 A San Mateo CA 9740 PACIFIC BELL 722      
650-554 A San Mateo CA 9740 PACIFIC BELL 722      
650-638 A San Mateo CA 9740 PACIFIC BELL 722      
650-655 A San Mateo CA 9740 PACIFIC BELL 722      

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

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