Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 605 [Rate centres in NPA 605] [Dial plan for NPA 605]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-257 A Nisland SD BISNSDXADS0  1689 WEST RIVER COOPERATIVE TELEPHONE COMPANY 640      

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

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