Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: CLNCMTMARS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
406-933 A Helena MT 9636 QWEST CORPORATION 648      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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