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: 220

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
310-220 A Hawthorne CA BLTNCAADPS2  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 730      
310-220 0 Hawthorne CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2004-10-19   
310-220 1 Hawthorne CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2005-07-21   
310-220 2 Hawthorne CA IRVNCASM1MD  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 730   2000-04-11   
310-220 3 Hawthorne CA BLTNCAADPS2  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 730      
310-220 4 Hawthorne CA LSANCA54DS7  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 730   2003-01-11   
310-220 5 Hawthorne CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2004-08-19   
310-220 6 Hawthorne CA   829J PAETEC ITEL, LLC 730   2000-04-03   
310-220 7 Hawthorne CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730   2003-06-02   
310-220 8 Hawthorne CA GRDNCA02KMD  7139 TELEPORT COMMUNICATIONS AMERICA, LLC - CA 730   2003-09-08   
310-220 9 Hawthorne CA BLTNCAADGMD  6006 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA 730   2003-07-07   

Last updated: Sat, 02 May 2026 12:20:53 UTC

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