Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 531 [Rate centres in NPA 531] [Dial plan for NPA 531]

NXX: 437

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
531-437 A Omaha NE   597J COMPUTER TELEPHONY INNOVATIONS INC. DBA VOXTELESYS 644   2026-05-02   
531-437 0 Omaha NE   597J COMPUTER TELEPHONY INNOVATIONS INC. DBA VOXTELESYS 644   2026-05-02   

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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