Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
918-356 A MNFROKXADS0  1982 CIMARRON TEL. CO. 538      

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

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