Local Calling Guide

Area code/prefix search

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NPA: 740 [Rate centres in NPA 740] [Dial plan for NPA 740]

NXX: 531

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
740-531 A Thornville OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2025-01-17   
740-531 0 Thornville OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2007-01-08   
740-531 1 Thornville OH   145J TERRA NOVA TELECOM INC. 324   2024-12-05   
740-531 2 Thornville OH   145J TERRA NOVA TELECOM INC. 324   2025-08-29   
740-531 3 Thornville OH   145J TERRA NOVA TELECOM INC. 324   2026-09-12   

Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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