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: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-255 A Mason City IA DESMIAITX6X  6529 T-MOBILE USA, INC. 632      
641-255 0 Mason City IA   985E BANDWIDTH.COM CLEC, LLC - IA 632   2022-07-16   
641-255 1 Mason City IA   985E BANDWIDTH.COM CLEC, LLC - IA 632   2022-08-13   
641-255 2 Mason City IA   985E BANDWIDTH.COM CLEC, LLC - IA 632   2022-08-15   
641-255 3 Mason City IA   221F ONVOY, LLC - IA 632   2023-08-11   
641-255 4 Mason City IA   221F ONVOY, LLC - IA 632   2023-08-11   
641-255 5 Mason City IA   6529 T-MOBILE USA, INC. 632   2022-06-12   
641-255 6 Mason City IA   6529 T-MOBILE USA, INC. 632   2022-06-12   
641-255 7 Mason City IA   6529 T-MOBILE USA, INC. 632   2022-06-12   
641-255 8 Mason City IA   6529 T-MOBILE USA, INC. 632   2022-06-12   
641-255 9 Mason City IA   6529 T-MOBILE USA, INC. 632   2022-06-12   

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

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