Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 618 [Rate centres in NPA 618] [Dial plan for NPA 618]

NXX: 427

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
618-427 A Brownstown IL BRTWILXERS0  1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-427 0 Brownstown IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-427 1 Brownstown IL   224C ONVOY, LLC 520   2019-07-29   
618-427 2 Brownstown IL   224C ONVOY, LLC 520   2018-08-20   
618-427 3 Brownstown IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-427 4 Brownstown IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 520   2017-10-15   
618-427 5 Brownstown IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-427 6 Brownstown IL   508J CENTURYLINK COMMUNICATIONS, LLC 520   2016-01-21   
618-427 7 Brownstown IL   5562 METROPCS, INC. 520   2021-10-13   
618-427 8 Brownstown IL   224C ONVOY, LLC 520   2019-07-29   
618-427 9 Brownstown IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      

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

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