Looking up a complete telephone number? Try Number Sleuth, a simplified interface for this lookup.

Input an Area Code (required) followed by the Prefix, or Exchange (optional):
-
If you were a paid member, you could be loading this into any version of Excel or Access (or any other software that understands CSV) right now for less than you paid for your breakfast or lunch today. If you are a member please login to access this and other functionality.

🔎 Tip: Click any Company, OCN, Rate Center, or CLLI to explore related telecom data

npa-nxxState/ProvinceCompanyFRNRMDOCNRate CenterCLLIAssign DateMisc
406-866MTQWEST CORPORATION0003746757RMD00063899636GREATFALLSULM MTMARS100/00/0000Prefix Type: RBOC
Switch Name: ULM
Switch Type: WECO 5ESS Remote (5A RSM)
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: ULM MTMARS1))
🕘 Prefix History
🔎 Explore Carrier Information
406-866 is split into 1,000-number blocks - detail below
406-866-0XXXMTCHARTER IP ENABLED SERVICES, LLCN/A792KGREATFALLSNOCLLIKNOWN03/01/2006Prefix Type: IPES
Switch Name: N/A
Switch Type: N/A
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 Prefix History
🔎 Explore Carrier Information
406-866-1XXXMTONVOY, LLC - MT (Sinch)0004323028RMD0001966453FGREATFALLSNOCLLIKNOWN03/29/2024Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 Prefix History
🔎 Explore Carrier Information
406-866-2XXXMTQWEST CORPORATION0003746757RMD00063899636GREATFALLSULM MTMARS1N/APrefix Type: RBOC
Switch Name: ULM
Switch Type: WECO 5ESS Remote (5A RSM)
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: ULM MTMARS1))
🕘 Prefix History
🔎 Explore Carrier Information
406-866-3XXXMTQWEST CORPORATION0003746757RMD00063899636GREATFALLSULM MTMARS1N/APrefix Type: RBOC
Switch Name: ULM
Switch Type: WECO 5ESS Remote (5A RSM)
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: ULM MTMARS1))
🕘 Prefix History
🔎 Explore Carrier Information
406-866-6XXXMTBOOST SUBSCRIBERCO L.L.C.0037698057RMD0031843490JGREATFALLSNOCLLIKNOWN07/12/2023Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 Prefix History
🔎 Explore Carrier Information
406-866-8XXXMTT-MOBILE USA, INC. (T-Mobile US, Inc)0017078262RMD00190516529GREATFALLSGRFLMTMAGMD09/25/2023Prefix Type: PCS
Switch Name: N/A
Switch Type: N/A
LATA: Great Falls MT (648)
Tandem: N/A
🔧 Explore Switch(CLLI: GRFLMTMAGMD))
🕘 Prefix History
🔎 Explore Carrier Information
This information is not guaranteed to be accurate. User assumes all risk for any loss or gain resulting from use of this data.
Although I strive for accuracy and prompt updates of changed information, it is possible that there may be errors. If you see one, could you please report it?
Please report all errors, flames, questions, suggestions, and thanks to Paul Timmins
L'exactitude de ces renseignements n'est pas garantie. L'utilisateur assume l'entière responsabilité des pertes ou des gains découlant de l'utilisation de ces données.
Bien que je m'efforce d'assurer l'exactitude des informations et de les mettre à jour rapidement, des erreurs peuvent subsister. Si vous en voyez une, veuillez me la signaler.
Veuillez adresser vos commentaires, remarques, questions, suggestions et remerciements à Paul Timmins
Please see the Frequently Asked Questions page if you have any questions.
Copyright ©2001-2026, Paul Timmins/Timmins Technologies, LLC. All rights reserved
Website Design and User Interface ©2010, Adam Botbyl/Revolutionary Solutions, LLC.
Colocation generously provided by Clear Rate Communications, Inc
Has this site changed your life? Made your job easier? I always love Fanmail and Suggestions.