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: 590

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-590 A Wasco CA BKFDCA12XRX  671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 734      
661-590 0 Wasco CA   649C ONVOY, LLC - CA 734   2024-03-07   
661-590 1 Wasco CA   649C ONVOY, LLC - CA 734   2024-07-15   
661-590 2 Wasco CA   649C ONVOY, LLC - CA 734   2024-07-15   
661-590 6 Wasco CA   6010 NEW CINGULAR WIRELESS PCS, LLC 734   2024-11-22   
661-590 7 Wasco CA   671J U.S. TELEPACIFIC CORP. DBA TPX COMMUNICATIONS 734   2022-08-15   
661-590 8 Wasco CA   649C ONVOY, LLC - CA 734   2024-06-07   
661-590 9 Wasco CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 734   2024-05-12   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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