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: 550

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-550 A Big Butte CA LSANCA039MD  981E BANDWIDTH.COM CLEC, LLC - CA 730      
661-550 0 Big Butte CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2021-11-21   
661-550 1 Big Butte CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2022-02-25   
661-550 2 Big Butte CA   981E BANDWIDTH.COM CLEC, LLC - CA 730   2022-03-24   
661-550 7 Big Butte CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2024-11-19   
661-550 8 Big Butte CA   624H ONVOY SPECTRUM, LLC 730   2024-01-04   
661-550 9 Big Butte CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 730   2022-11-18   

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

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