Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 240 [Rate centres in NPA 240] [Dial plan for NPA 240]

NXX: 573

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-573 A Washington Zone 15 MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236      
240-573 0 Washington Zone 15 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-08-11   
240-573 1 Washington Zone 15 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-10-22   
240-573 2 Washington Zone 15 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2012-04-05   
240-573 3 Washington Zone 15 MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2026-09-27   
240-573 4 Washington Zone 15 MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2026-11-05   
240-573 5 Washington Zone 15 MD   071F BANDWIDTH.COM CLEC, LLC - MD 236   2026-08-15   
240-573 6 Washington Zone 15 MD BTVLMD12CMA  5562 METROPCS, INC. 236   2014-12-29   
240-573 7 Washington Zone 15 MD MCLNVA23DS4  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 236   2012-06-09   
240-573 8 Washington Zone 15 MD BTVLMD12CMA  5562 METROPCS, INC. 236   2014-12-29   
240-573 9 Washington Zone 15 MD   515J IP HORIZON LLC 236   2016-05-31   

Last updated: Sun, 01 Nov 2026 02:11:49 UTC

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