Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 641 [Rate centres in NPA 641] [Dial plan for NPA 641]

NXX: 660

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-660 A Oskaloosa IA CNVLIABC1MD  6266 UNITED STATES CELLULAR - IA 632      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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