Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 507 [Rate centres in NPA 507] [Dial plan for NPA 507]

NXX: 723

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
507-723 A Springfield MN NWULMNXNDS0  1502 WESTERN TEL. CO. 620      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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