Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 660 [Rate centres in NPA 660] [Dial plan for NPA 660]

NXX: 399

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-399 A South Seymour MO SYMRIAXORS8  1178 WINDSTREAM IOWA COMMUNICATIONS, INC. 632      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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