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: 657

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
320-657 A Graceville MN STCDMNTOXXX  719F MCC TELEPHONY OF MINNESOTA, LLC - MN 626      
320-657 1 Graceville MN   2629 FEDERATED TELEPHONE COOPERATIVE - MN 626   2014-11-29   
320-657 2 Graceville MN   184D ONVOY, LLC - MN 626   2021-03-11   
320-657 3 Graceville MN   624H ONVOY SPECTRUM, LLC 626   2024-12-19   
320-657 4 Graceville MN   5256 LEVEL 3 COMMUNICATIONS, LLC - MN 626   2023-02-25   
320-657 5 Graceville MN   184D ONVOY, LLC - MN 626   2020-01-30   
320-657 6 Graceville MN   719F MCC TELEPHONY OF MINNESOTA, LLC - MN 626   2010-07-11   
320-657 7 Graceville MN   508J CENTURYLINK COMMUNICATIONS, LLC 626   2017-06-20   
320-657 8 Graceville MN   184D ONVOY, LLC - MN 626   2021-03-11   

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

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