Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Alta, WY

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
307-353 A DRGSIDMADS2  2214 COLUMBINE TELCO DBA SILVER STAR COMMUNICATIONS 652      

Last updated: Sun, 17 May 2026 03:26:51 UTC

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