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: 990

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-990 A Monmouth IL MCMBILXDXFX  114J EXIANT COMMUNICATIONS LLC 977   2026-05-15   
309-990 0 Monmouth IL MCMBILXDXFX  114J EXIANT COMMUNICATIONS LLC 977   2026-05-15   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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