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: 485

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-485 A Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2025-07-03   
307-485 0 Casper WY CSPRWYMAXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 654   2025-07-04   
307-485 1 Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2025-09-21   
307-485 2 Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2025-09-21   
307-485 3 Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2026-01-15   
307-485 4 Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2026-01-15   
307-485 7 Casper WY   081F BANDWIDTH.COM CLEC, LLC - WY 654   2026-09-13   
307-485 8 Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2025-07-03   
307-485 9 Casper WY CSPRWYMAXEX  6529 T-MOBILE USA, INC. 654   2025-07-03   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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