Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Alta, IA

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
712-200 A ALTAIA01RS0  3097 ALTA MUNICIPAL UTILITIES - IA 630      
712-284 A STLKIATCDS0  9631 QWEST CORPORATION 630      
712-284 0   751F MCC TELEPHONY OF IOWA, LLC - IA 630   2010-04-23   
712-284 1   9631 QWEST CORPORATION 630      
712-284 2   9631 QWEST CORPORATION 630      
712-284 3   444G AUREON COMMUNICATIONS, LLC 630   2021-09-26   
712-284 4   145J TERRA NOVA TELECOM INC. 630   2025-05-17   
712-284 5   9877 LEVEL 3 COMMUNICATIONS, LLC - IA 630   2022-12-10   
712-284 7   508J CENTURYLINK COMMUNICATIONS, LLC 630   2016-12-23   
712-284 8   515J IP HORIZON LLC 630   2025-10-03   
712-284 9   145J TERRA NOVA TELECOM INC. 630   2026-01-04   
712-491 A   7421 AT&T - LOCAL 630   2025-11-07   
712-491 9   7421 AT&T - LOCAL 630   2025-11-07   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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