Local Calling Guide

Area code/prefix search

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NPA: 309 [Rate centres in NPA 309] [Dial plan for NPA 309]

NXX: 457

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-457 A Monmouth IL MNMOILXDDS0  1183 CITIZENS TELECOM CO ILLINOIS-FRONTIER CITIZENS -IL 977      

Last updated: Tue, 30 May 2023 01:08:39 UTC

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