Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 320 [Rate centres in NPA 320] [Dial plan for NPA 320]

NXX: 853

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
320-853 A Madison MN STCDMNTOXXX  719F MCC TELEPHONY OF MINNESOTA, LLC - MN 626      
320-853 0 Madison MN   719F MCC TELEPHONY OF MINNESOTA, LLC - MN 626   2010-05-16   
320-853 1 Madison MN   184D ONVOY, LLC - MN 626   2016-07-29   
320-853 2 Madison MN   184D ONVOY, LLC - MN 626   2021-05-24   
320-853 3 Madison MN   184D ONVOY, LLC - MN 626   2015-06-19   
320-853 5 Madison MN   184D ONVOY, LLC - MN 626   2022-08-07   
320-853 6 Madison MN   8405 TELEPORT COMMUNICATIONS AMERICA, LLC - MN 626   2022-07-11   
320-853 7 Madison MN   5256 LEVEL 3 COMMUNICATIONS, LLC - MN 626   2017-06-21   
320-853 8 Madison MN   073H TELNYX LLC 626   2020-07-20   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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