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: 594

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-594 A Shafter CA BKFDCA01X2X  6529 T-MOBILE USA, INC. 734      
661-594 0 Shafter CA   939H COMMIO, LLC 734   2022-11-10   
661-594 1 Shafter CA   649C ONVOY, LLC - CA 734   2023-10-30   
661-594 2 Shafter CA   649C ONVOY, LLC - CA 734   2023-10-30   
661-594 3 Shafter CA   649C ONVOY, LLC - CA 734   2023-10-30   
661-594 4 Shafter CA   649C ONVOY, LLC - CA 734   2023-10-30   
661-594 5 Shafter CA   649C ONVOY, LLC - CA 734   2023-10-30   
661-594 6 Shafter CA   6010 NEW CINGULAR WIRELESS PCS, LLC 734   2025-07-04   
661-594 8 Shafter CA   6010 NEW CINGULAR WIRELESS PCS, LLC 734   2024-12-08   
661-594 9 Shafter CA   6529 T-MOBILE USA, INC. 734   2022-11-05   

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

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