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]

NXX: 323

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-323 A Sharptown MD   829J PAETEC ITEL, LLC 242   2025-04-01   
443-323 0 Sharptown MD   876D ONVOY, LLC - MD 242   2020-04-30   
443-323 1 Sharptown MD   876D ONVOY, LLC - MD 242   2020-07-04   
443-323 2 Sharptown MD   876D ONVOY, LLC - MD 242   2020-07-04   
443-323 3 Sharptown MD   318J COMCAST IP PHONE, LLC 242   2006-07-31   
443-323 4 Sharptown MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2019-05-02   
443-323 5 Sharptown MD   145J TERRA NOVA TELECOM INC. 242   2024-02-15   
443-323 6 Sharptown MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2019-05-02   
443-323 7 Sharptown MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-06-17   
443-323 8 Sharptown MD   2593 CORE COMMUNICATIONS, INC.- MD 242   2018-06-17   
443-323 9 Sharptown MD   829J PAETEC ITEL, LLC 242      

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

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