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: 720

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-720 A Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 0 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 1 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 2 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 3 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 4 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 5 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 6 Naugatuck CT HRFRCT03HMD  073H TELNYX LLC 920   2018-05-02   
203-720 7 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      
203-720 8 Naugatuck CT SMFRCTPU4MD  4800 LEVEL 3 COMMUNICATIONS, LLC - CT 920   2012-04-07   
203-720 9 Naugatuck CT NGTCCT00DS0  9147 SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 920      

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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