Local Calling Guide

Area code/prefix search

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

NXX: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-604 A Norwalk CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-604 0 Norwalk CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-03-12   
203-604 1 Norwalk CT NWHNCT030MD  3722 CONVERSENT COMMUNICATIONS OF CONNECTICUT, LLC - CT 920   2003-12-06   
203-604 2 Norwalk CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2004-09-11   
203-604 3 Norwalk CT MDTWCTNIGT1  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2014-05-17   
203-604 4 Norwalk CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2010-06-16   
203-604 5 Norwalk CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2011-02-03   
203-604 6 Norwalk CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-11-03   
203-604 7 Norwalk CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2011-08-18   
203-604 8 Norwalk CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2002-07-16   
203-604 9 Norwalk CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2005-06-04   

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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