Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 408 [Rate centres in NPA 408] [Dial plan for NPA 408]

NXX: 312

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
408-312 A San Martin CA SNJUCACL00Z  490J DISH WIRELESS, LLC 722      
408-312 0 San Martin CA   490J DISH WIRELESS, LLC 722   2023-07-13   
408-312 1 San Martin CA   6529 T-MOBILE USA, INC. 722   2024-01-22   
408-312 2 San Martin CA   624H ONVOY SPECTRUM, LLC 722   2024-01-15   
408-312 3 San Martin CA   624H ONVOY SPECTRUM, LLC 722   2024-01-15   
408-312 4 San Martin CA   624H ONVOY SPECTRUM, LLC 722   2024-01-15   
408-312 5 San Martin CA   624H ONVOY SPECTRUM, LLC 722   2024-01-15   
408-312 6 San Martin CA   6529 T-MOBILE USA, INC. 722   2024-01-22   
408-312 7 San Martin CA   6529 T-MOBILE USA, INC. 722   2024-01-22   
408-312 8 San Martin CA   6529 T-MOBILE USA, INC. 722   2024-01-22   
408-312 9 San Martin CA   6529 T-MOBILE USA, INC. 722   2024-01-22   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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