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: 306

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
641-306 A Thompson IA   9877 LEVEL 3 COMMUNICATIONS, LLC - IA 632   2026-06-19   
641-306 7 Thompson IA   9877 LEVEL 3 COMMUNICATIONS, LLC - IA 632   2026-06-19   

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

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