Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 309 [Rate centres in NPA 309] [Dial plan for NPA 309]

NXX: 728

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-728 A Towanda IL TWNDILXDDS0  1038 FRONTIER COMMUNICATIONS OF ILLINOIS, INC. 366      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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