Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 650 [Rate centres in NPA 650] [Dial plan for NPA 650]

NXX: 634

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
650-634 A South San Francisco CA SNBUCA02DS0  9740 PACIFIC BELL 722      
650-634 0 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 1 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 2 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 3 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 4 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 5 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 6 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 7 South San Francisco CA   9740 PACIFIC BELL 722      
650-634 8 South San Francisco CA   516C AT&T CORP. 722   2014-04-16   
650-634 9 South San Francisco CA   9740 PACIFIC BELL 722      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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