Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 810 [Rate centres in NPA 810] [Dial plan for NPA 810]

NXX: 385

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-385 A Port Huron MI PTHRMINRRSA  9323 MICHIGAN BELL TEL CO 340      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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