Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 661 [Rate centres in NPA 661] [Dial plan for NPA 661]

NXX: 778

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-778 A Delano CA BKFDCA12DS1  7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 734      
661-778 0 Delano CA   337E BRIGHT HOUSE NTWS INFORMATION SVCS (CALIFORNIA) CA 734   2007-07-26   
661-778 1 Delano CA   7718 LEVEL 3 TELECOM OF CALIFORNIA, LP - CA 734      
661-778 2 Delano CA   5562 METROPCS, INC. 734   2007-08-14   
661-778 3 Delano CA   5562 METROPCS, INC. 734   2005-02-07   
661-778 4 Delano CA   5562 METROPCS, INC. 734   2007-08-14   
661-778 5 Delano CA   5562 METROPCS, INC. 734   2006-08-12   
661-778 6 Delano CA   5562 METROPCS, INC. 734   2005-11-12   
661-778 7 Delano CA   5562 METROPCS, INC. 734   2004-04-29   
661-778 8 Delano CA   6010 NEW CINGULAR WIRELESS PCS, LLC 734   2005-11-18   
661-778 9 Delano CA   5562 METROPCS, INC. 734   2003-07-15   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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