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: RNDPMTXCDS0

Remotes:

Switch Switch name Switch type
BLNGMT30RS0  BILLINGS  DE4 
CSTRMTXCRS1  NORTH CUSTER  DCO 
GRRNMTXCRS1  GRASS RANGE  DCO 
LAVNMTXCRS1  LAVINA  DCO 
MELSMTXCRS1  MELSTONE  DCO 
MSLSMTXCRS1  MUSSELSHELL  DCO 
ROY MTXCRS1  ROY  DCO 
RYGTMTXBRS1  RYEGATE  DCO 
RYGTMTXCRS1  RYEGATE  DCO 
WNTTMTXCRS0  WINNETT  DS 
NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-323 A Roundup MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-358 A Melstone MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-428 A Grass Range MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-429 A Winnett MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-464 A Roy MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-636 A Lavina MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-856 A Custer MT 2246 MID-RIVERS TEL. COOP., INC. 650      
406-947 A Musselshell MT 2246 MID-RIVERS TEL. COOP., INC. 650      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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