Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 310 [Rate centres in NPA 310] [Dial plan for NPA 310]

NXX: 309

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-309 A Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 0 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730   2002-12-14   
310-309 1 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730   2006-04-24   
310-309 2 Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 3 Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 4 Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 5 Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 6 Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 7 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730   2002-12-14   
310-309 8 Santa Monica: Santa Monica DA CA LSANCA03DS3  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730      
310-309 9 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730   2002-12-14   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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