Note: This is a listing of deprecated systems. These systems are either no longer in use or have been superceded by another system.
| System Name | Type | Flavor | City | County | Updated |
|---|---|---|---|---|---|
| Aberdeen Proving Ground (Motorola) | Motorola | Type II SmartZone | Aberdeen | Harford | 2012-08-04 |
| Allegany County Governmental Services | LTR | Standard | Various | Multi-County [2] | 2012-09-19 |
| Allegany County Public Safety | LTR | Passport | Cumberland | Allegany | 2020-04-18 |
| Andrews Air Force Base (Motorola) | Motorola | Type II Smartnet | Andrews AFB | Prince George's | 2008-05-20 |
| ARINC (BWI Airport) | Motorola | Type I | Baltimore | Anne Arundel | 2007-05-27 |
| Baltimore City (Motorola) | Motorola | Type II SmartZone | Baltimore | Baltimore | 2011-04-11 |
| Baltimore County Public Safety | Motorola | Type II Smartnet | Baltimore | Baltimore | 2012-10-04 |
| Baltimore County Services | Motorola | Type II Smartnet | Baltimore County | Baltimore | 2012-10-04 |
| Baltimore Gas and Electric (BGE) | Motorola | Type II Smartnet | Various | Multi-County [8] | 2018-07-20 |
| Calvert Cliffs Nuclear Power Plant (P16) | Motorola | Type II Smartnet | Lusby | Calvert | 2021-03-05 |
| Calvert County (P16) | Motorola | Type II Smartnet | Various | Calvert | 2021-05-29 |
| Carroll County (Project 16) | Motorola | Type II Smartnet | Westminster | Carroll | 2015-07-06 |
| Cecil County | EDACS | Extended Addressing w/ESK | Elkton | Cecil | 2020-08-15 |
| Champion Communication (Baltimore 1) | LTR | Standard | Baltimore | Baltimore | 2018-07-20 |
| Champion Communication (Frederick) | LTR | Standard | Frederick | Frederick | 2016-09-28 |
| Chesapeake Detention Facility | EDACS | Standard | Baltimore | Baltimore | 2022-04-29 |
| Cumberland Fire Department | LTR | Standard | Cumberland | Allegany | 2020-04-18 |
| Delmarva Power / Atlantic City Electric | Motorola | Type II SmartZone | Various | Multi-County [23] | 2023-01-08 |
| Dorchester County | Motorola | Type II SmartZone | Dorchester County | Dorchester | 2021-03-20 |
| Dorchester County (LTR MultiNet) | LTR | MultiNet | Dorchester County | Dorchester | 2004-11-24 |
| FedExField | LTR | Standard | Landover | Prince George's | 2023-11-03 |
| FleetTalk - Silver Spring (Connect Plus) | DMR | Motorola Connect Plus (TRBO) | Silver Spring | Montgomery | 2013-07-25 |
| Fort Detrick (400 MHz) | Motorola | Type II Smartnet | Frederick | Frederick | 2005-08-11 |
| Fort Meade (400 MHz) | Motorola | Type II Smartnet | Fort Meade | Anne Arundel | 2007-08-27 |
| Frederick County (Project 16) | Motorola | Type II Smartnet | Frederick County | Frederick | 2013-04-11 |
| Gaylord National Resort and Convention Center | LTR | Standard | Oxen Hill | Prince George's | 2018-07-20 |
| General Motors Research | Motorola | Type II Smartnet | Baltimore | Baltimore | 2006-02-22 |
| Goddard Space Flight Center | EDACS | Standard | Greenbelt | Prince George's | 2020-12-07 |
| Goddard Space Flight Center | Motorola | Type II Smartnet | Greenbelt | Prince George's | 2010-08-14 |
| Harford County | Motorola | Type II SmartZone | Bel Air | Harford | 2015-04-24 |
| Howard County (Project 16) | Motorola | Type II SmartZone | Ellicott City | Howard | 2020-03-03 |
| James J. Rowley Training Center | Motorola | Type II SmartZone | Laurel | Prince George's | 2023-05-03 |
| Joint Base Andrews | Project 25 | Phase I | Camp Springs | Prince George's | 2015-09-02 |
| Joint National Capital Region (Fort Detrick) | Project 25 | Phase I | Frederick | Frederick | 2011-09-29 |
| Joint National Capital Region (Fort Meade) | Project 25 | Phase I | Fort Meade | Multi-County [2] | 2011-09-29 |
| Joint National Capital Region (Germantown) | Project 25 | Phase I | Germantown | Montgomery | 2011-09-29 |
| Joint National Capital Region (National Geospatial-Intelligence Agency) | Project 25 | Phase I | Various | Multi-County [4] | 2012-10-28 |
| Joint National Capital Region (Silver Hill) | Project 25 | Phase I | Silver Hill | Prince George's | 2011-09-29 |
| Joint National Capital Region (Walter Reed Army Medical Center) | Project 25 | Phase I | Washington/Forest Glen | Multi-County [2] | 2011-09-29 |
| Loyola University Maryland | LTR | Standard | Baltimore | Baltimore | 2021-08-28 |
| Maryland Port Administration | Motorola | Type II Smartnet | Dundalk | Multi-County [2] | 2021-01-25 |
| Maryland Transit Administration | Motorola | Type II Smartnet | Baltimore | Multi-County [4] | 2023-03-15 |
| Meritus Medical Center (LTR) | LTR | Standard | Hagerstown | Washington | 2019-02-20 |
| Montgomery County, MD (P16) | Motorola | Type II SmartZone | Various | Montgomery | 2021-03-10 |
| Montgomery County, MD Schools Bus Maintenance | DMR | Motorola Capacity Plus Single Site (TRBO) | Rockville | Montgomery | 2021-09-19 |
| National Institutes of Health | Motorola | Type II SmartZone | Various | Multi-County [2] | 2020-07-23 |
| National Institutes of Health (Bethesda) | Motorola | Type II Smartnet | Bethesda | Montgomery | 2007-11-24 |
| National Institutes of Health (Unknown Location) | Motorola | Type II | Unknown | UNKNOWN | 2007-06-06 |
| National Security Agency | Project 25 | Phase I | Fort Meade | Anne Arundel | 2006-06-04 |
| Naval Air Station Patuxent River | Motorola | Type II Smartnet | Patuxent River | St. Mary's | 2011-06-15 |
| Naval District of Washington | EDACS | Networked Standard | Washington | Multi-County [3] | 2011-01-23 |
| Nextel (Baltimore 800 MHz) | Motorola | Type I | Baltimore | Baltimore | 2009-12-27 |
| Nextel (Baltimore 900 MHz 1) | Motorola | Type II Smartnet | Baltimore | Baltimore | 2018-07-20 |
| Nextel (Baltimore 900 MHz 2) | Motorola | Type II Smartnet | Baltimore | Baltimore | 2018-07-20 |
| Nextel (Catonsville) | Motorola | Type II Smartnet | Catonsville | Baltimore | 2009-12-26 |
| Ocean City | EDACS | Networked Standard | Ocean City | Worcester | 2014-04-26 |
| Otakon 2011 | DMR | Motorola Capacity Plus Single Site (TRBO) | Baltimore | Baltimore | 2016-05-22 |
| Prince George's County (North) | EDACS | Standard | Greenbelt | Prince George's | 2013-07-23 |
| Prince George's County (South) | EDACS | Standard | Brandywine | Prince George's | 2013-07-23 |
| Quicken Loans National (2016) | DMR | Motorola Capacity Plus Single Site (TRBO) | Bethesda | Montgomery | 2020-07-01 |
| Salisbury Public Safety | Motorola | Type II Smartnet | Salisbury | Wicomico | 2020-10-30 |
| Somerset County, MD (EDACS) | EDACS | Standard | Somerset | Somerset | 2020-04-18 |
| Southern Maryland Electric Cooperative | DMR | Motorola Capacity Plus Multi Site (TRBO) | Various | Multi-County [3] | 2017-05-14 |
| St. Mary's County (EDACS) | EDACS | Standard | Leonardtown | St. Mary's | 2013-08-25 |
| Teltronic (Whaleyville) | LTR | Standard | Whaleyville | Worcester | 2021-12-11 |
| Teltronic, Inc. | LTR | Standard | Beltsville | Multi-County [6] | 2007-04-27 |
| TWR Comms (460 MHz) | LTR | Standard | Frederick | Frederick | 2019-07-26 |
| Unidentified Federal Motorola A73B | Motorola | Type II SmartZone | Washington | Multi-County [3] | 2016-03-26 |
| United Airlines (BWI Airport) | Motorola | Type II Smartnet | Baltimore | Anne Arundel | 2012-09-04 |
| University of Maryland, Baltimore | Motorola | Type II Smartnet | Baltimore | Baltimore | 2021-01-25 |
| US Department of Commerce | Motorola | Type II Smartnet | Baltimore | Baltimore | 2012-02-28 |
| Washington County Public Safety (Project 25) | Project 25 | Phase I | Hagerstown | Washington | 2009-12-24 |
| Washington Gas Light Company | Motorola | Type II Smartnet | Various | Multi-County [9] | 2016-04-02 |
| Wicomico County Public Safety | Motorola | Type II Smartnet | Salisbury | Wicomico | 2019-01-13 |
| Worcester County / Ocean City | EDACS | Networked Standard | Snow Hill | Worcester | 2019-04-08 |
| Yellow Cab of Baltimore | LTR | Standard | Baltimore | Baltimore | 2024-02-12 |