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: 431

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
650-431 A San Mateo CA OKLECAZV1MD  6529 T-MOBILE USA, INC. 722      
650-431 0 San Mateo CA   649C ONVOY, LLC - CA 722   2016-01-13   
650-431 1 San Mateo CA   649C ONVOY, LLC - CA 722   2016-01-13   
650-431 2 San Mateo CA   649C ONVOY, LLC - CA 722   2016-02-22   
650-431 3 San Mateo CA   649C ONVOY, LLC - CA 722   2016-02-22   
650-431 4 San Mateo CA   6010 NEW CINGULAR WIRELESS PCS, LLC 722   2016-02-19   
650-431 5 San Mateo CA   6010 NEW CINGULAR WIRELESS PCS, LLC 722   2016-02-19   
650-431 6 San Mateo CA   6529 T-MOBILE USA, INC. 722   2016-03-31   
650-431 7 San Mateo CA   649C ONVOY, LLC - CA 722   2016-04-24   
650-431 8 San Mateo CA   6529 T-MOBILE USA, INC. 722   2015-11-07   
650-431 9 San Mateo CA   6529 T-MOBILE USA, INC. 722   2015-11-07   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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