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: 591

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
661-591 A Glennville CA BKFDCA119MD  8826 LEVEL 3 COMMUNICATIONS, LLC - CA 734      
661-591 0 Glennville CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 734      
661-591 1 Glennville CA   515J IP HORIZON LLC 734   2006-09-28   
661-591 2 Glennville CA   515J IP HORIZON LLC 734   2006-09-28   
661-591 3 Glennville CA   624H ONVOY SPECTRUM, LLC 734   2024-01-05   
661-591 4 Glennville CA   8826 LEVEL 3 COMMUNICATIONS, LLC - CA 734   2005-07-30   
661-591 5 Glennville CA   649C ONVOY, LLC - CA 734   2021-03-04   
661-591 6 Glennville CA   649C ONVOY, LLC - CA 734   2021-03-04   
661-591 8 Glennville CA   373F PEERLESS NETWORK OF CALIFORNIA, LLC - CA 734   2018-12-20   
661-591 9 Glennville CA   073H TELNYX LLC 734   2018-07-10   

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

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