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: 297

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-297 A Eureka Rural MT ERKRMTXCDS1  3959 INTERBEL TELEPHONE COOPERATIVE, INC. - MT 648      

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

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