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: 788

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
631-788 A Fishers Island NY FSISNYXFDS0  0095 FISHERS ISLAND TEL. CORP. 921      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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