Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 597

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-597 A Waldorf MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236      
301-597 0 Waldorf MD   624H ONVOY SPECTRUM, LLC 236   2022-03-11   
301-597 1 Waldorf MD   876D ONVOY, LLC - MD 236   2022-04-25   
301-597 2 Waldorf MD   624H ONVOY SPECTRUM, LLC 236   2022-03-21   
301-597 3 Waldorf MD   624H ONVOY SPECTRUM, LLC 236   2022-03-21   
301-597 4 Waldorf MD   876D ONVOY, LLC - MD 236   2022-04-25   
301-597 5 Waldorf MD   624H ONVOY SPECTRUM, LLC 236   2022-03-11   
301-597 6 Waldorf MD   624H ONVOY SPECTRUM, LLC 236   2022-03-11   
301-597 7 Waldorf MD   876D ONVOY, LLC - MD 236   2022-04-25   
301-597 8 Waldorf MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-03-10   
301-597 9 Waldorf MD   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-03-10   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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