Input a CLLI:

Tip: A Partial CLLI can be entered, but must contain a minimum of the first 6 characters. I.E. 'DLLSTX'

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

npa-nxxStateCompanyFRNRMDOCNRate CenterCLLIAssign DateMisc
231-743MIMICHIGAN BELL TEL CO (AT&T)N/A9323MARIONMARNMIMNRSA00/00/0000Prefix Type: RBOC
Switch Name: MARION
Switch Type: N/A
LATA: Grand Rapids MI (348)
Tandem: TRCYMIMN20T
🔧 Explore Switch(CLLI: MARNMIMNRSA))
231-743 is split into 1,000-number blocks - detail below
231-743-2XXXMIMICHIGAN BELL TEL CO (AT&T)N/A9323MARIONMARNMIMNRSAN/APrefix Type: RBOC
Switch Name: MARION
Switch Type: N/A
LATA: Grand Rapids MI (348)
Tandem: TRCYMIMN20T
🔧 Explore Switch(CLLI: MARNMIMNRSA))
231-743-6XXXMIMICHIGAN BELL TEL CO (AT&T)N/A9323MARIONMARNMIMNRSAN/APrefix Type: RBOC
Switch Name: MARION
Switch Type: N/A
LATA: Grand Rapids MI (348)
Tandem: TRCYMIMN20T
🔧 Explore Switch(CLLI: MARNMIMNRSA))
231-743-9XXXMIMICHIGAN BELL TEL CO (AT&T)N/A9323MARIONMARNMIMNRSAN/APrefix Type: RBOC
Switch Name: MARION
Switch Type: N/A
LATA: Grand Rapids MI (348)
Tandem: TRCYMIMN20T
🔧 Explore Switch(CLLI: MARNMIMNRSA))
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