Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 424 [Rate centres in NPA 424] [Dial plan for NPA 424]

NXX: 392

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
424-392 A Redondo CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
424-392 0 Redondo CA   6529 T-MOBILE USA, INC. 730   2015-04-08   
424-392 1 Redondo CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2015-03-18   
424-392 2 Redondo CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2015-03-18   
424-392 3 Redondo CA   6529 T-MOBILE USA, INC. 730   2014-12-25   
424-392 4 Redondo CA   6529 T-MOBILE USA, INC. 730   2014-12-25   
424-392 5 Redondo CA   6529 T-MOBILE USA, INC. 730   2014-12-25   
424-392 6 Redondo CA   649C ONVOY, LLC - CA 730   2015-09-09   
424-392 7 Redondo CA   649C ONVOY, LLC - CA 730   2015-09-09   
424-392 8 Redondo CA   515J IP HORIZON LLC 730   2015-09-19   
424-392 9 Redondo CA   6529 T-MOBILE USA, INC. 730   2014-12-25   

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

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