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: 476

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-476 A Laramie WY   450F ONVOY, LLC - WY 654   2025-03-02   
307-476 0 Laramie WY   450F ONVOY, LLC - WY 654   2025-03-02   
307-476 1 Laramie WY   450F ONVOY, LLC - WY 654   2025-04-11   
307-476 8 Laramie WY   450F ONVOY, LLC - WY 654   2025-05-10   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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