Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Waterloo, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
667-374 7   876D ONVOY, LLC - MD 238   2022-09-25   
667-374 8   624H ONVOY SPECTRUM, LLC 238   2022-02-11   
667-374 9   624H ONVOY SPECTRUM, LLC 238   2022-02-11   

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Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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