Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: CLFDMNXCRS0

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
320-669 A Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 0 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 1 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 3 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 4 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 6 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 7 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 8 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      
320-669 9 Clarkfield MN 1123 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 626      

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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