Local Calling Guide

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NPA: 641 [Rate centres in NPA 641] [Dial plan for NPA 641]

NXX: 310

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-310 A Marshalltown IA DESMIADTFMD  221F ONVOY, LLC - IA 632   2024-04-29   
641-310 0 Marshalltown IA DESMIADTFMD  221F ONVOY, LLC - IA 632   2024-04-29   
641-310 1 Marshalltown IA DESMIADTX1X  624H ONVOY SPECTRUM, LLC 632   2024-12-15   
641-310 3 Marshalltown IA   6570 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 632   2025-08-18   
641-310 6 Marshalltown IA DESMIAITX7X  695G IMON COMMUNICATIONS, LLC - IA 632   2024-10-25   
641-310 8 Marshalltown IA   515J IP HORIZON LLC 632   2025-09-26   
641-310 9 Marshalltown IA DESMIADTXKX  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 632   2024-12-15   

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

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