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: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-421 A Redondo CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
310-421 0 Redondo CA SNMNCAXPX3Z  649C ONVOY, LLC - CA 730      
310-421 1 Redondo CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2000-12-27   
310-421 2 Redondo CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2004-09-01   
310-421 3 Redondo CA   7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730   2001-10-19   
310-421 4 Redondo CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2003-01-11   
310-421 5 Redondo CA   6529 T-MOBILE USA, INC. 730   2003-06-01   
310-421 6 Redondo CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730   2003-06-01   
310-421 7 Redondo CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730   2003-06-01   
310-421 8 Redondo CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2010-03-23   
310-421 9 Redondo CA LSANCAJWDS9  373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730      

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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