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: 278

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-278 A Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 0 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 1 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 2 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 3 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 4 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 5 Ansonia-Derby CT HRFRCTASDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 920   2003-06-18   
203-278 6 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-278 7 Ansonia-Derby CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2007-10-22   
203-278 8 Ansonia-Derby CT   145J TERRA NOVA TELECOM INC. 920   2022-04-17   
203-278 9 Ansonia-Derby CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      

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

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