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: 575

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-575 A Macomb IL CLCHILXDDS2  342F MTC COMMUNICATIONS, INC. - IL 977      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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