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: 397

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-397 A Hanna WY CHYNWYMAX6X  6010 NEW CINGULAR WIRELESS PCS, LLC 654      
307-397 8 Hanna WY CHYNWYMAX6X  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2021-12-20   
307-397 9 Hanna WY CHYNWYMAX6X  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2021-12-20   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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