Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 601 [Rate centres in NPA 601] [Dial plan for NPA 601]

NXX: 343

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
601-343 A Heidelberg MS HDLBMSMAXMD  4664 CENTURYLINK COMMUNICATIONS LLC - MS 482      
601-343 0 Heidelberg MS JCSNMSCPXMZ  719E ONVOY, LLC - MS 482   2021-02-23   
601-343 3 Heidelberg MS   145J TERRA NOVA TELECOM INC. 482   2025-07-16   
601-343 9 Heidelberg MS HDLBMSMAXMD  4664 CENTURYLINK COMMUNICATIONS LLC - MS 482      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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