Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Keystone, OK

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
918-243 A MNFROKXADS0  1982 CIMARRON TEL. CO. 538      

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

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