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: 670

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-670 A Fairfield CT BLFDCTAP2MD  6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920      
203-670 0 Fairfield CT   639C ONVOY, LLC - CT 920   2023-08-18   
203-670 1 Fairfield CT   515J IP HORIZON LLC 920   2022-07-22   
203-670 2 Fairfield CT   639C ONVOY, LLC - CT 920   2022-09-17   
203-670 3 Fairfield CT   624H ONVOY SPECTRUM, LLC 920   2022-05-23   
203-670 4 Fairfield CT   624H ONVOY SPECTRUM, LLC 920   2022-05-23   
203-670 5 Fairfield CT   624H ONVOY SPECTRUM, LLC 920   2022-05-23   
203-670 6 Fairfield CT   624H ONVOY SPECTRUM, LLC 920   2022-02-13   
203-670 7 Fairfield CT   624H ONVOY SPECTRUM, LLC 920   2022-02-13   
203-670 8 Fairfield CT   624H ONVOY SPECTRUM, LLC 920   2022-02-13   
203-670 9 Fairfield CT   6624 OMNIPOINT COMMUNICATIONS, INC. - CT 920   2022-01-27   

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

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