Local Calling Guide

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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 533

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-533 A Guilford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-533 0 Guilford CT HRFRCTBCDS1  639C ONVOY, LLC - CT 920   2019-02-18   
203-533 1 Guilford CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-02-28   
203-533 2 Guilford CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2012-10-06   
203-533 3 Guilford CT HRFRCTASDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 920   2012-02-01   
203-533 4 Guilford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2004-04-16   
203-533 5 Guilford CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920   2004-12-18   
203-533 6 Guilford CT   829J PAETEC ITEL, LLC 920   2009-12-11   
203-533 7 Guilford CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920   2012-12-17   
203-533 8 Guilford CT HRFRCT0380Z  539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2013-05-03   
203-533 9 Guilford CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2008-11-29   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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