Local Calling Guide

Area code/prefix search

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OCN: 876D ONVOY, LLC - MD

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NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
301-450 6 Washington Zone 3 MD VINNVACBDS0  236   2022-09-17   
301-450 7 Washington Zone 3 MD VINNVACBDS0  236   2022-09-17   
301-450 8 Washington Zone 3 MD VINNVACBDS0  236   2022-09-17   
301-453 4 Kitzmiller MD CMLDMDCMEMD  240   2016-09-12   
301-453 8 Kitzmiller MD CMLDMDCMEMD  240   2016-09-12   
301-458 3 Washington Zone 4 MD VINNVACBDS0  236   2016-02-29   
301-477 0 Washington Zone 13 MD VINNVACBDS0  236   2024-09-15   
301-477 8 Washington Zone 13 MD VINNVACBDS0  236   2018-01-14   
301-477 9 Washington Zone 13 MD VINNVACBDS0  236   2018-01-14   
301-478 8 Flintstone MD CMLDMDCMEMD  240   2016-09-12   
301-478 9 Flintstone MD CMLDMDCMEMD  240   2016-09-12   
301-479 0 Washington Zone 13 MD VINNVACBDS0  236   2024-11-04   
301-479 5 Washington Zone 13 MD VINNVACBDS0  236   2023-06-17   
301-479 6 Washington Zone 13 MD VINNVACBDS0  236   2023-06-17   
301-479 8 Washington Zone 13 MD VINNVACBDS0  236   2023-06-17   
301-479 9 Washington Zone 13 MD VINNVACBDS0  236   2023-06-17   
301-485 2 Washington Zone 6 MD VINNVACBDS0  236   2016-03-02   
301-485 4 Washington Zone 6 MD VINNVACBDS0  236   2016-04-28   
301-485 5 Washington Zone 6 MD VINNVACBDS0  236   2015-06-27   
301-507 0 Washington Zone 13 MD VINNVACBDS0  236   2024-02-24   
301-507 1 Washington Zone 13 MD VINNVACBDS0  236   2024-02-24   
301-507 2 Washington Zone 13 MD VINNVACBDS0  236   2024-02-24   
301-507 3 Washington Zone 13 MD VINNVACBDS0  236   2024-02-24   
301-507 4 Washington Zone 13 MD VINNVACBDS0  236   2024-07-27   
301-507 7 Washington Zone 13 MD VINNVACBDS0  236   2024-07-27   
301-507 8 Washington Zone 13 MD VINNVACBDS0  236   2024-07-27   
301-507 9 Washington Zone 13 MD VINNVACBDS0  236   2024-07-27   
301-513 8 Washington Zone 13 MD VINNVACBDS0  236   2024-09-15   
301-517 6 Washington Zone 10 MD VINNVACBDS0  236   2018-01-13   
301-517 9 Washington Zone 10 MD VINNVACBDS0  236   2018-01-13   
301-539 6 La Plata MD VINNVACBDS0  236   2022-08-21   
301-547 7 Washington Zone 2 MD VINNVACBDS0  236   2020-12-03   
301-550 2 Washington Zone 10 MD VINNVACBDS0  236   2022-10-15   
301-558 2 Washington Zone 13 MD   236   2025-09-28   
301-558 3 Washington Zone 13 MD   236   2025-09-28   
301-558 4 Washington Zone 13 MD   236   2025-09-28   
301-558 5 Washington Zone 13 MD   236   2025-08-29   
301-558 6 Washington Zone 13 MD   236   2025-09-28   
301-558 8 Washington Zone 13 MD   236   2025-08-29   
301-569 9 Gaithersburg MD VINNVACBDS0  236   2012-04-05   
301-579 7 Brandywine MD VINNVACBDS0  236   2016-03-03   
301-579 8 Brandywine MD VINNVACBDS0  236   2016-03-03   
301-591 7 Gaithersburg MD VINNVACBDS0  236   2021-02-18   
301-597 1 Waldorf MD VINNVACBDS0  236   2022-04-25   
301-597 4 Waldorf MD VINNVACBDS0  236   2022-04-25   
301-597 7 Waldorf MD VINNVACBDS0  236   2022-04-25   
301-603 3 Washington Zone 11 MD VINNVACBDS0  236   2015-06-27   
301-610 3 Washington Zone 10 MD VINNVACBDS0  236   2020-04-30   
301-635 0 Washington Zone 5 MD VINNVACBDS0  236   2023-05-16   
301-635 1 Washington Zone 5 MD VINNVACBDS0  236   2023-05-16   

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Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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