Local Calling Guide

Area code/prefix search

Search by area code/prefix (NPA/NXX) or OCN

  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Last updated: Sat, 23 Nov 2013 02:28:03 UTC

How to use this page

NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 645

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA Eff date Disc date Map
203-645 A New Haven CT 4036 NEW CINGULAR WIRELESS PCS, LLC - DC [link] 920


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