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: 439

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-439 A Cheshire CT HRFRCTCR3MD  318J COMCAST IP PHONE, LLC 920      
203-439 0 Cheshire CT   318J COMCAST IP PHONE, LLC 920      
203-439 1 Cheshire CT   5562 METROPCS, INC. 920   2006-09-26   
203-439 2 Cheshire CT   318J COMCAST IP PHONE, LLC 920   2006-09-19   
203-439 3 Cheshire CT   639C ONVOY, LLC - CT 920   2016-08-11   
203-439 4 Cheshire CT   639C ONVOY, LLC - CT 920   2016-08-11   
203-439 5 Cheshire CT   639C ONVOY, LLC - CT 920   2017-09-29   
203-439 6 Cheshire CT   199F BANDWIDTH.COM CLEC, LLC - CT 920   2016-07-14   
203-439 7 Cheshire CT   318J COMCAST IP PHONE, LLC 920      
203-439 8 Cheshire CT   318J COMCAST IP PHONE, LLC 920   2014-10-10   
203-439 9 Cheshire CT   318J COMCAST IP PHONE, LLC 920      

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

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