Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 313 [Rate centres in NPA 313] [Dial plan for NPA 313]

NXX: 606

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
313-606 A Detroit Zone 5 MI CMPTMIIFCM0  9748 AMERICAN MESSAGING SERVICES, LLC 340      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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