Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 870 [Rate centres in NPA 870] [Dial plan for NPA 870]

NXX: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
870-437 A Alpena AR ALPEARXARS0  1726 TRI-COUNTY TEL. CO., INC. 528      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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