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: 593

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-593 A Santa Clarita: Newhall-Castaic DA CA TRNECAGB7MD  6529 T-MOBILE USA, INC. 730      
661-593 0 Santa Clarita: Newhall-Castaic DA CA   6010 NEW CINGULAR WIRELESS PCS, LLC 730   2016-09-12   
661-593 1 Santa Clarita: Newhall-Castaic DA CA   973E RACE TELECOMMUNICATIONS, INC. - CA 730   2016-11-20   
661-593 2 Santa Clarita: Newhall-Castaic DA CA   899D METROPCS NETWORKS, LLC 730   2016-12-31   
661-593 3 Santa Clarita: Newhall-Castaic DA CA   899D METROPCS NETWORKS, LLC 730   2017-04-17   
661-593 4 Santa Clarita: Newhall-Castaic DA CA   649C ONVOY, LLC - CA 730   2017-06-10   
661-593 5 Santa Clarita: Newhall-Castaic DA CA   073H TELNYX LLC 730   2017-06-02   
661-593 6 Santa Clarita: Newhall-Castaic DA CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2019-05-26   
661-593 7 Santa Clarita: Newhall-Castaic DA CA   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 730   2016-09-12   
661-593 8 Santa Clarita: Newhall-Castaic DA CA   6529 T-MOBILE USA, INC. 730   2016-12-09   
661-593 9 Santa Clarita: Newhall-Castaic DA CA   6529 T-MOBILE USA, INC. 730   2016-09-11   

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

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