Local Calling Guide

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Washington Zone 13, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-479 5 VINNVACBDS0  876D ONVOY, LLC - MD 236   2023-06-17   
301-479 6 VINNVACBDS0  876D ONVOY, LLC - MD 236   2023-06-17   
301-479 7   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-479 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2023-06-17   
301-479 9 VINNVACBDS0  876D ONVOY, LLC - MD 236   2023-06-17   
301-486 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 0 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 1 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 2 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 3 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 4 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 5   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-486 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 7 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-486 8   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-486 9   2593 CORE COMMUNICATIONS, INC.- MD 236   2018-10-23   
301-488 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 0 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 1 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 2   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-04-29   
301-489 3 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 4 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 5 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 7 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 8 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-489 9 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-506 A SLSPMDSSX6X  6630 SPOK, INC. 236      
301-507 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-507 0 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-02-24   
301-507 1 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-02-24   
301-507 2 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-02-24   
301-507 3 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-02-24   
301-507 4 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-27   
301-507 5 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-507 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-507 7 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-27   
301-507 8 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-27   
301-507 9 VINNVACBDS0  876D ONVOY, LLC - MD 236   2024-07-27   
301-510 A SLSPMDSSX6X  6630 SPOK, INC. 236      
301-513 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-513 0 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-513 1 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-513 2   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-06-01   
301-513 3 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-513 4   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2025-06-01   
301-513 5 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-513 6 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      
301-513 7 CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      

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Last updated: Sat, 02 May 2026 12:20:53 UTC

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