Local Calling Guide

Area code/prefix search

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

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
918-788 A WLCHOKXADS0  1966 ATLAS TEL. CO. 538      

Last updated: Fri, 10 Jul 2026 02:55:48 UTC

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