Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 307

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-307 A Fairfield CT SMFRCTDSDS0  7230 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 920      
203-307 0 Fairfield CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2011-05-27   
203-307 1 Fairfield CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-12-19   
203-307 2 Fairfield CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-12-19   
203-307 3 Fairfield CT   829J PAETEC ITEL, LLC 920   2005-12-19   
203-307 4 Fairfield CT   829J PAETEC ITEL, LLC 920   2006-09-21   
203-307 5 Fairfield CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-03-05   
203-307 6 Fairfield CT SMFRCTDSDS0  7230 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 920   2005-03-24   
203-307 7 Fairfield CT SMFRCTDSDS0  7230 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 920   2005-03-24   
203-307 8 Fairfield CT SMFRCTDSDS0  7230 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 920   2005-03-24   
203-307 9 Fairfield CT SMFRCTDSDS0  7230 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 920   2005-03-24   

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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