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: 331

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
320-331 A Brownton MN OSSEMNXODMD  593K MCC TELEPHONY LLC 628      
320-331 0 Brownton MN   184D ONVOY, LLC - MN 628   2019-02-25   
320-331 1 Brownton MN   593K MCC TELEPHONY LLC 628   2010-05-15   
320-331 2 Brownton MN   184D ONVOY, LLC - MN 628   2020-11-07   
320-331 3 Brownton MN   184D ONVOY, LLC - MN 628   2015-06-18   
320-331 5 Brownton MN   184D ONVOY, LLC - MN 628   2021-03-11   
320-331 6 Brownton MN   184D ONVOY, LLC - MN 628   2022-10-01   
320-331 7 Brownton MN   508J CENTURYLINK COMMUNICATIONS, LLC 628   2014-11-18   
320-331 8 Brownton MN   184D ONVOY, LLC - MN 628   2019-02-25   
320-331 9 Brownton MN   073H TELNYX LLC 628   2020-07-09   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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