Local Calling Guide

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

NXX: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-557 A Bloomington IL BLTNILXDDS0  1015 FRONTIER NORTH, INC. - IL 366      
309-557 0 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 1 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 2 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 3 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 4 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 5 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 6 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 7 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      
309-557 8 Bloomington IL   1015 FRONTIER NORTH, INC. - IL 366      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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