Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

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 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: Wed, 04 Mar 2026 03:00:52 UTC

Sponsored by: LES.NET

Like this site? We accept donations via PayPal.