Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-340 A Bensenville IL   224C ONVOY, LLC 358   2025-12-27   
331-340 0 Bensenville IL   224C ONVOY, LLC 358   2025-12-27   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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