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   6529 T-MOBILE USA, INC. 654   2025-07-03   
307-485 0 Casper WY   6010 NEW CINGULAR WIRELESS PCS, LLC 654   2025-07-04   
307-485 1 Casper WY   6529 T-MOBILE USA, INC. 654   2025-09-21   
307-485 2 Casper WY   6529 T-MOBILE USA, INC. 654   2025-09-21   
307-485 3 Casper WY   6529 T-MOBILE USA, INC. 654   2026-01-15   
307-485 4 Casper WY   6529 T-MOBILE USA, INC. 654   2026-01-15   
307-485 5 Casper WY   6566 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 654   2026-03-16   
307-485 6 Casper WY   6566 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - WY 654   2026-04-08   
307-485 8 Casper WY   6529 T-MOBILE USA, INC. 654   2025-07-03   
307-485 9 Casper WY   6529 T-MOBILE USA, INC. 654   2025-07-03   

Last updated: Tue, 31 Mar 2026 13:56:49 UTC

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