Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 727

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-727 A Mountain City TN MTCYTNXARS0  4510 UNITED TELEPHONE-SOUTHEAST-TN DBA CENTURYLINK - TN 956      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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