Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Mark, IA

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
641-929 A MARKIAXO1MD  1129 CITIZENS MUTUAL TELEPHONE COOPERATIVE 632      

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

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