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: 372

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-372 A Douglas WY CHYNWYMAX2X  450F ONVOY, LLC - WY 654      
307-372 0 Douglas WY   624H ONVOY SPECTRUM, LLC 654   2021-11-26   
307-372 1 Douglas WY   624H ONVOY SPECTRUM, LLC 654   2021-11-26   
307-372 2 Douglas WY   450F ONVOY, LLC - WY 654   2020-10-10   
307-372 3 Douglas WY   450F ONVOY, LLC - WY 654   2020-10-10   
307-372 4 Douglas WY   450F ONVOY, LLC - WY 654   2020-12-19   
307-372 5 Douglas WY   450F ONVOY, LLC - WY 654   2020-12-19   
307-372 6 Douglas WY   450F ONVOY, LLC - WY 654   2021-03-02   
307-372 7 Douglas WY   450F ONVOY, LLC - WY 654   2021-03-02   
307-372 8 Douglas WY   450F ONVOY, LLC - WY 654   2021-03-02   
307-372 9 Douglas WY   081F BANDWIDTH.COM CLEC, LLC - WY 654   2020-10-11   

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

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