Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: MRTHOKXADS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
580-266 A Martha OK 2025 SOUTHWEST OKLAHOMA TEL. CO. 536      

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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