Local Calling Guide

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Diamond Bar, CA

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
909-979 4 RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730   2004-03-17   
909-979 5 LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730      
909-979 6 LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730      
909-979 7 RVSDCALBCM4  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2006-10-17   
909-979 8 LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2006-03-03   
909-979 9 LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730   2010-07-04   

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Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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