Local Calling Guide

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

NXX: 528

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-528 A Waterbury CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-528 0 Waterbury CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920      
203-528 1 Waterbury CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 2 Waterbury CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2005-10-16   
203-528 3 Waterbury CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920   2007-08-21   
203-528 4 Waterbury CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920   2007-08-21   
203-528 5 Waterbury CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 6 Waterbury CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-12-17   
203-528 7 Waterbury CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2006-09-15   
203-528 8 Waterbury CT MDTWCTNIBMD  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   

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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