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: 428

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-428 A Santa Monica: Santa Monica DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730      
310-428 0 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
310-428 1 Santa Monica: Santa Monica DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730      
310-428 2 Santa Monica: Santa Monica DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730      
310-428 3 Santa Monica: Santa Monica DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730      
310-428 4 Santa Monica: Santa Monica DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730      
310-428 5 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
310-428 6 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
310-428 7 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
310-428 8 Santa Monica: Santa Monica DA CA TRNECAGB7MD  899D METROPCS NETWORKS, LLC 730      
310-428 9 Santa Monica: Santa Monica DA CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      

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

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