Local Calling Guide

Area code/prefix search

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Geraldine, MT

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
406-737 A FTBNMTXCDS0  3310 TRIANGLE TEL. COOP. ASSN., INC. 648      

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

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