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: 428

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-428 A Mason City IA MSCYIATCDS0  9631 QWEST CORPORATION 632      
641-428 0 Mason City IA   985E BANDWIDTH.COM CLEC, LLC - IA 632   2017-08-06   
641-428 1 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 2 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 3 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 4 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 5 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 6 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 7 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 8 Mason City IA   9631 QWEST CORPORATION 632   2010-10-01   
641-428 9 Mason City IA   444G AUREON COMMUNICATIONS, LLC 632   2013-07-16   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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