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: 639

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-639 A Lodge Grass MT LDGSMTXCRS1  2250 PROJECT TEL. CO., INC. 650      

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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