Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Darlington, MO

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
660-666 A BTHNMOXADS0  1888 GRAND RIVER MUTUAL TEL CO 524      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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