Local Calling Guide

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Washington Zone 13 (Baltimore LATA), MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-307 9 BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2020-11-07   

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Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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