Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 734 [Rate centres in NPA 734] [Dial plan for NPA 734]

NXX: 817

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
734-817 A Ann Arbor MI CMPTMIIFCM0  9748 AMERICAN MESSAGING SERVICES, LLC 340      

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

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