Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 631 [Rate centres in NPA 631] [Dial plan for NPA 631]

NXX: 251

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
631-251 A Sag Harbor NY NYCMNY83DSZ  4006 LEVEL 3 COMMUNICATIONS, LLC - NY 132      
631-251 0 Sag Harbor NY   473G TELENGY L.L.C. - NY 132   2012-02-27   
631-251 1 Sag Harbor NY   384C ONVOY, LLC- NY 132   2023-08-11   
631-251 2 Sag Harbor NY   4006 LEVEL 3 COMMUNICATIONS, LLC - NY 132      
631-251 3 Sag Harbor NY   384C ONVOY, LLC- NY 132   2021-11-03   
631-251 4 Sag Harbor NY   384C ONVOY, LLC- NY 132   2021-11-03   
631-251 5 Sag Harbor NY   384C ONVOY, LLC- NY 132   2022-02-18   
631-251 6 Sag Harbor NY   4006 LEVEL 3 COMMUNICATIONS, LLC - NY 132   2004-10-28   
631-251 7 Sag Harbor NY   7133 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - NY 132   2005-11-02   
631-251 8 Sag Harbor NY   384C ONVOY, LLC- NY 132   2022-01-01   

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

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