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: 433

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-433 A Branford CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920      
203-433 0 Branford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2008-05-15   
203-433 1 Branford CT HRFRCT03Y4X  829J PAETEC ITEL, LLC 920   2004-12-06   
203-433 2 Branford CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-12-25   
203-433 3 Branford CT HRFRCTASDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 920   2008-08-01   
203-433 4 Branford CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920   2008-09-01   
203-433 5 Branford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2011-01-31   
203-433 6 Branford CT HRFRCTBCDS1  639C ONVOY, LLC - CT 920   2020-07-05   
203-433 7 Branford CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2012-09-22   
203-433 8 Branford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-12-09   
203-433 9 Branford CT   639C ONVOY, LLC - CT 920   2026-09-27   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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