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: 303

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-303 A Redondo CA GRDNCA01DS0  7480 PACIFIC BELL (COMPETITIVE) 730      
310-303 0 Redondo CA   6529 T-MOBILE USA, INC. 730   2003-03-26   
310-303 1 Redondo CA   6529 T-MOBILE USA, INC. 730   2003-12-07   
310-303 2 Redondo CA   6529 T-MOBILE USA, INC. 730   2003-12-07   
310-303 3 Redondo CA   7480 PACIFIC BELL (COMPETITIVE) 730      
310-303 4 Redondo CA   6529 T-MOBILE USA, INC. 730   2003-12-07   
310-303 5 Redondo CA   7480 PACIFIC BELL (COMPETITIVE) 730   2001-08-31   
310-303 6 Redondo CA   7480 PACIFIC BELL (COMPETITIVE) 730   2001-08-31   
310-303 7 Redondo CA   7480 PACIFIC BELL (COMPETITIVE) 730   2001-08-31   
310-303 8 Redondo CA   6529 T-MOBILE USA, INC. 730   2003-12-07   
310-303 9 Redondo CA   6529 T-MOBILE USA, INC. 730   2005-08-05   

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

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