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: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
618-437 A Ina IL INA ILXERS0  1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-437 0 Ina IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-437 1 Ina IL   073H TELNYX LLC 520   2020-07-11   
618-437 2 Ina IL   224C ONVOY, LLC 520   2021-02-26   
618-437 3 Ina IL   508J CENTURYLINK COMMUNICATIONS, LLC 520   2016-02-11   
618-437 4 Ina IL   224C ONVOY, LLC 520   2018-08-20   
618-437 5 Ina IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      
618-437 6 Ina IL   984E BANDWIDTH.COM CLEC, LLC - IL 520   2019-12-09   
618-437 7 Ina IL   224C ONVOY, LLC 520   2019-07-29   
618-437 8 Ina IL   224C ONVOY, LLC 520   2019-07-29   
618-437 9 Ina IL   1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 520      

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

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