Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 406 [Rate centres in NPA 406] [Dial plan for NPA 406]

NXX: 618

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-618 A Missoula MT   520K TDS METROCOM, LLC 648   2025-12-05   
406-618 0 Missoula MT   6010 NEW CINGULAR WIRELESS PCS, LLC 648   2026-01-03   
406-618 2 Missoula MT   520K TDS METROCOM, LLC 648   2025-12-05   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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