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

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-523 8 Norwalk CT   7143 TELEPORT COMMUNICATIONS AMERICA, LLC - CT 920      
203-523 9 Norwalk CT   5562 METROPCS, INC. 920   2015-01-27   
203-524 A Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-524 0 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-524 1 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2010-08-11   
203-524 2 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-524 3 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-524 4 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-524 5 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-524 6 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2010-08-11   
203-524 7 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2008-09-19   
203-524 8 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2010-05-22   
203-524 9 Stamford CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2010-05-22   
203-525 A Waterbury CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920      
203-526 A Bridgeport CT BLFDCTAP2MD  5562 METROPCS, INC. 920      
203-526 0 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 1 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 2 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 3 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 4 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 5 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 6 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 7 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 8 Bridgeport CT   5562 METROPCS, INC. 920      
203-526 9 Bridgeport CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-527 A Waterbury CT PRSPCT00RS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-527 0 Waterbury CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-02-28   
203-527 1 Waterbury CT   5562 METROPCS, INC. 920   2006-01-20   
203-527 2 Waterbury CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2009-11-27   
203-527 3 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2006-11-22   
203-527 4 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2006-11-22   
203-527 5 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2006-11-22   
203-527 6 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2008-02-20   
203-527 7 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2008-02-20   
203-527 8 Waterbury CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920   2006-07-07   
203-527 9 Waterbury CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-528 A Waterbury CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-528 0 Waterbury CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-528 1 Waterbury CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 2 Waterbury CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2005-10-16   
203-528 3 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2007-08-21   
203-528 4 Waterbury CT   318J COMCAST IP PHONE, LLC 920   2007-08-21   
203-528 5 Waterbury CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 6 Waterbury CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 7 Waterbury CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2006-09-15   
203-528 8 Waterbury CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 9 Waterbury CT   145J TERRA NOVA TELECOM INC. 920   2022-04-17   
203-529 A Wilton CT NWHNCT02X5X  7421 AT&T - LOCAL 920      
203-529 0 Wilton CT   145J TERRA NOVA TELECOM INC. 920   2025-07-24   
203-529 1 Wilton CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-12-25   
203-529 2 Wilton CT   4950 CABLEVISION LIGHTPATH, INC. - CT 920   2003-05-27   
203-529 3 Wilton CT   612K CSC VOICE, LLC 920   2009-09-19   
203-529 4 Wilton CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2004-04-16   
203-529 5 Wilton CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2013-04-07   
203-529 6 Wilton CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2012-03-10   
203-529 7 Wilton CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2014-02-08   
203-529 8 Wilton CT   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2013-05-04   
203-529 9 Wilton CT   7421 AT&T - LOCAL 920      
203-530 A New Haven CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920      
203-531 A Byram CT PTCHNYPCDS0  9104 VERIZON NEW YORK, INC. 132      
203-532 A Byram CT PTCHNYPCDS0  9104 VERIZON NEW YORK, INC. 132      
203-532 0 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 1 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 2 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 3 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 4 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 5 Byram CT   612K CSC VOICE, LLC 132   2003-11-15   
203-532 6 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 7 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-532 8 Byram CT   829J PAETEC ITEL, LLC 132   2001-09-03   
203-532 9 Byram CT   9104 VERIZON NEW YORK, INC. 132      
203-533 A Guilford CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-533 0 Guilford CT   639C ONVOY, LLC - CT 920   2019-02-18   
203-533 1 Guilford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-02-28   
203-533 2 Guilford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2012-10-06   
203-533 3 Guilford CT   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 920   2012-02-01   
203-533 4 Guilford CT   4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2004-04-16   
203-533 5 Guilford CT   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   318J COMCAST IP PHONE, LLC 920   2012-12-17   
203-533 8 Guilford CT   539F PEERLESS NETWORK OF CONNECTICUT, LLC - CT 920   2013-05-03   
203-533 9 Guilford CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2008-11-29   
203-534 A Bridgeport CT BRPTCT01DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 0 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 1 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 2 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 3 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 4 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 5 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 6 Bridgeport CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2005-09-24   
203-534 7 Bridgeport CT   9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-534 8 Bridgeport CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2005-09-24   
203-534 9 Bridgeport CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2005-09-24   
203-535 A New Haven CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920      
203-535 0 New Haven CT   318J COMCAST IP PHONE, LLC 920      
203-535 1 New Haven CT   318J COMCAST IP PHONE, LLC 920   2006-04-16   
203-535 2 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2007-07-05   
203-535 3 New Haven CT   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2005-03-23   
203-535 4 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2007-02-02   
203-535 5 New Haven CT   6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2007-02-02   

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Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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