Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-998 9 Parkville MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2014-12-31   
443-999 A Baltimore MD BLTMMDCH06T  9212 VERIZON MARYLAND, INC. 238      

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Last updated: Sat, 10 Oct 2026 15:24:20 UTC

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