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: 937

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-937 A Cambridge IL CMBRILXDDS0  0983 CAMBRIDGE TEL. CO. 634      

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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