Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 970 [Rate centres in NPA 970] [Dial plan for NPA 970]

NXX: 428

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
970-428 A Montrose CO GDJTCOCK2MD  775D NUCLA-NATURITA TELEPHONE COMPANY 656      

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

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