Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 220 [Rate centres in NPA 220] [Dial plan for NPA 220]

NXX: 666

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
220-666 A Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324      
220-666 0 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2019-02-22   
220-666 1 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2019-02-22   
220-666 2 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2020-06-05   
220-666 3 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2020-09-04   
220-666 4 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2020-09-04   
220-666 5 Baltimore OH CLMBOHLT7MD  073H TELNYX LLC 324   2021-01-21   
220-666 6 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2017-12-07   
220-666 7 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2020-12-13   
220-666 8 Baltimore OH CLMBOHLT1MD  464C ONVOY, LLC - OH 324   2020-12-13   
220-666 9 Baltimore OH HLRDOHEJGT0  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 324   2017-12-18   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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