Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Carter, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-734 A FRFDMTXCDS1  2255 3 RIVERS TEL. COOP., INC. 648      

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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