Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 3959 INTERBEL TELEPHONE COOPERATIVE, INC. - MT

NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
406-297 A Eureka Rural MT ERKRMTXCDS1  648      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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