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: SNBUCA02DS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
650-244 A South San Francisco CA 9740 PACIFIC BELL 722      
650-246 A South San Francisco CA 9740 PACIFIC BELL 722      
650-266 A South San Francisco CA 9740 PACIFIC BELL 722      
650-583 A South San Francisco CA 9740 PACIFIC BELL 722      
650-588 A South San Francisco CA 9740 PACIFIC BELL 722      
650-589 A South San Francisco CA 9740 PACIFIC BELL 722      
650-827 A South San Francisco CA 9740 PACIFIC BELL 722      
650-871 A South San Francisco CA 9740 PACIFIC BELL 722      
650-872 A South San Francisco CA 9740 PACIFIC BELL 722      
650-873 A South San Francisco CA 9740 PACIFIC BELL 722      
650-952 A South San Francisco CA 9740 PACIFIC BELL 722      

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

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