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
203-635CTLEVEL 3 COMMUNICATIONS, LLC - CT (Lumen Technologies, Inc)0015338122RMD00061124800WESTPORTSMFRCTPU4MD00/00/0000Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: SMFRCTPU4MD))
🕘 Prefix History
🔎 Explore Carrier Information
203-635 is split into 1,000-number blocks - detail below
203-635-0XXXCTLEVEL 3 COMMUNICATIONS, LLC - CT (Lumen Technologies, Inc)0015338122RMD00061124800WESTPORTSMFRCTPU4MD12/20/2004Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: SMFRCTPU4MD))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-1XXXCTPAETEC ITEL, LLC0015247810RMD0038378829JWESTPORTSMFRCTATXMD05/12/2005Prefix Type: IPES
Switch Name: STAMFORD
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: SMFRCTATXMD))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-2XXXCTBANDWIDTH.COM CLEC, LLC - CT (Bandwidth Inc.)0017042060RMD0003709199FWESTPORTNOCLLIKNOWN10/27/2014Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-3XXXCTNEW CINGULAR WIRELESS PCS, LLC - DC (AT&T)0003291192RMD00369094036WESTPORTMDTWCTNIBMD08/17/2011Prefix Type: WIRELESS
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: MDTWCTNIBMD))
🕘 Prefix History
🔎 Explore Carrier Information
📡 Find related FCC/ISED radio licenses
203-635-4XXXCTLEVEL 3 COMMUNICATIONS, LLC - CT (Lumen Technologies, Inc)0015338122RMD00061124800WESTPORTSMFRCTPU4MDN/APrefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: SMFRCTPU4MD))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-5XXXCTLEVEL 3 COMMUNICATIONS, LLC - CT (Lumen Technologies, Inc)0015338122RMD00061124800WESTPORTSMFRCTPU4MD08/02/2012Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: SMFRCTPU4MD))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-6XXXCTLEVEL 3 COMMUNICATIONS, LLC - CT (Lumen Technologies, Inc)0015338122RMD00061124800WESTPORTSMFRCTPU4MD02/08/2012Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: SMFRCTPU4MD))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-7XXXCTBANDWIDTH.COM CLEC, LLC - CT (Bandwidth Inc.)0017042060RMD0003709199FWESTPORTNOCLLIKNOWN10/27/2014Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-8XXXCTPEERLESS NETWORK OF CONNECTICUT, LLC - CT (Infobip)N/AN/A539FWESTPORTNOCLLIKNOWN04/05/2013Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 Prefix History
🔎 Explore Carrier Information
203-635-9XXXCTPEERLESS NETWORK OF CONNECTICUT, LLC - CT (Infobip)N/AN/A539FWESTPORTNOCLLIKNOWN04/05/2013Prefix Type: CLEC
Switch Name: N/A
Switch Type: N/A
LATA: Connecticut (920)
Tandem: N/A
🔧 Explore Switch(CLLI: NOCLLIKNOWN))
🕘 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.