Local Calling Guide

Area code/prefix search

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NPA: 810 [Rate centres in NPA 810] [Dial plan for NPA 810]

NXX: 583

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-583 A Sandusky MI SFLDMIDC0MD  817J INTERACTIVE SERVICES NETWORK, INC. 340      

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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