Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 307 [Rate centres in NPA 307] [Dial plan for NPA 307]

NXX: 392

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-392 A Border WY BOISIDMAX2X  9416 LEVEL 3 COMMUNICATIONS, LLC - WY 652      
307-392 0 Border WY   450F ONVOY, LLC - WY 652   2012-12-13   
307-392 1 Border WY   450F ONVOY, LLC - WY 652   2012-12-13   
307-392 2 Border WY   9416 LEVEL 3 COMMUNICATIONS, LLC - WY 652   2012-11-09   
307-392 3 Border WY   450F ONVOY, LLC - WY 652   2012-12-13   
307-392 4 Border WY   9416 LEVEL 3 COMMUNICATIONS, LLC - WY 652   2006-08-12   
307-392 5 Border WY   450F ONVOY, LLC - WY 652   2019-09-07   
307-392 6 Border WY   508J CENTURYLINK COMMUNICATIONS, LLC 652   2014-07-29   
307-392 7 Border WY   450F ONVOY, LLC - WY 652   2007-04-27   
307-392 8 Border WY   450F ONVOY, LLC - WY 652   2011-06-05   
307-392 9 Border WY   073H TELNYX LLC 652   2019-03-01   

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

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