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.

Switch: BLNGMTMADS1

Remotes:

Switch Switch name Switch type
CLSTMTMARS1  COLSTRIP  5ER 
NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-237 A Billings MT 9636 QWEST CORPORATION 650      
406-238 A Billings MT 9636 QWEST CORPORATION 650      
406-245 A Billings MT 9636 QWEST CORPORATION 650      
406-247 A Billings MT 9636 QWEST CORPORATION 650      
406-248 A Billings MT 9636 QWEST CORPORATION 650      
406-252 A Billings MT 9636 QWEST CORPORATION 650      
406-254 A Billings MT 9636 QWEST CORPORATION 650      
406-255 A Billings MT 9636 QWEST CORPORATION 650      
406-256 A Billings MT 9636 QWEST CORPORATION 650      
406-259 A Billings MT 9636 QWEST CORPORATION 650      
406-413 A Billings MT 9636 QWEST CORPORATION 650      
406-657 A Billings MT 9636 QWEST CORPORATION 650      
406-896 A Billings MT 9636 QWEST CORPORATION 650      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.