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: 921

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-921 A Redondo CA RDBHCAXF37K  2319 FRONTIER CALIFORNIA INC. 730      
310-921 0 Redondo CA   899D METROPCS NETWORKS, LLC 730   2011-04-16   
310-921 1 Redondo CA   2319 FRONTIER CALIFORNIA INC. 730      
310-921 2 Redondo CA   2319 FRONTIER CALIFORNIA INC. 730      
310-921 3 Redondo CA   2319 FRONTIER CALIFORNIA INC. 730      
310-921 4 Redondo CA   2319 FRONTIER CALIFORNIA INC. 730      
310-921 5 Redondo CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2006-06-19   
310-921 6 Redondo CA   2319 FRONTIER CALIFORNIA INC. 730      
310-921 7 Redondo CA   829J PAETEC ITEL, LLC 730   2005-10-17   
310-921 8 Redondo CA   576C TIME WARNER CBL INFO SVCS (CA) DBA TIME WARNER CAB 730   2013-10-15   
310-921 9 Redondo CA   2319 FRONTIER CALIFORNIA INC. 730      

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

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