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: 564

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-564 A Stamford CT NWHNCT02X5X  7421 AT&T - LOCAL 920      
203-564 0 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2004-01-12   
203-564 1 Stamford CT NWHNCT02X5X  7421 AT&T - LOCAL 920      
203-564 2 Stamford CT   145J TERRA NOVA TELECOM INC. 920   2023-08-05   
203-564 3 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2004-04-16   
203-564 4 Stamford CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2014-09-06   
203-564 5 Stamford CT NWHNCT02X5X  7421 AT&T - LOCAL 920      
203-564 6 Stamford CT MDTWCTNIBMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 920   2004-08-08   
203-564 7 Stamford CT HRFRCTASBMD  6388 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 920   2014-09-06   
203-564 8 Stamford CT NWHNCT02X5X  7421 AT&T - LOCAL 920   2009-06-14   
203-564 9 Stamford CT HRFRCT0379Z  199F BANDWIDTH.COM CLEC, LLC - CT 920   2010-08-20   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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