Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 510 [Rate centres in NPA 510] [Dial plan for NPA 510]

NXX: 921

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
510-921 A Hayward CA SNFCCAFJDS0  7145 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 722      
510-921 0 Hayward CA   5562 METROPCS, INC. 722   2006-06-11   
510-921 1 Hayward CA   5562 METROPCS, INC. 722   2006-01-17   
510-921 2 Hayward CA   5562 METROPCS, INC. 722   2006-01-17   
510-921 3 Hayward CA   7145 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 722      
510-921 4 Hayward CA   5562 METROPCS, INC. 722   2006-01-19   
510-921 5 Hayward CA   7145 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 722      
510-921 6 Hayward CA   5562 METROPCS, INC. 722   2005-12-19   
510-921 7 Hayward CA   5562 METROPCS, INC. 722   2005-05-20   
510-921 8 Hayward CA   5562 METROPCS, INC. 722   2005-02-28   
510-921 9 Hayward CA   5562 METROPCS, INC. 722   2005-11-15   

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

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