Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: ALTONMXCRS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
575-336 A Alto NM 1193 VALOR TELECOM TX,LP-NM #2 DBA WINDSTREAM COMM SW 664      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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