Local Calling Guide

Area code/prefix search

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

NXX: 364

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-364 A Port Huron MI MYVIMIMNRSA  9323 MICHIGAN BELL TEL CO 340      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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