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: 435

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-435 A Sheridan WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2026-01-30   
307-435 7 Sheridan WY   114J EXIANT COMMUNICATIONS LLC 654   2026-05-23   
307-435 9 Sheridan WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2026-01-30   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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