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: 488

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
406-488 A Sidney MT SDNYMTAORS0  7830 MID-RIVERS TELEPHONE COOPERATIVE, INC. 650      

Last updated: Fri, 25 Jul 2025 03:21:23 UTC

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