List of Counties in Maryland
Maryland has 24 counties (including Baltimore City, which is independent of any county). The most populous counties are Montgomery County, Prince George’s County, Baltimore County, Baltimore City, Anne Arundel County, Howard County, Harford County, Frederick County, Carroll County, and Charles County. Montgomery and Prince George’s counties, part of the Washington, D.C. metropolitan area, are the largest by population. Baltimore City, although independent, remains one of the most populous areas in the state. These counties contribute significantly to Maryland’s economy, particularly through government, education, and technology.
List of All Counties in Maryland
- Allegany County, Maryland
- Anne Arundel County, Maryland
- Baltimore County, Maryland
- Calvert County, Maryland
- Caroline County, Maryland
- Carroll County, Maryland
- Cecil County, Maryland
- Charles County, Maryland
- Dorchester County, Maryland
- Frederick County, Maryland
- Garrett County, Maryland
- Harford County, Maryland
- Howard County, Maryland
- Kent County, Maryland
- Montgomery County, Maryland
- Prince George’s County, Maryland
- Queen Anne’s County, Maryland
- Saint Mary’s County, Maryland
- Somerset County, Maryland
- Talbot County, Maryland
- Washington County, Maryland
- Wicomico County, Maryland
- Worcester County, Maryland
1. Frederick County
Overview
Frederick County is the largest county in Maryland by land area and is located in the western part of the state. It borders Pennsylvania to the north and Virginia to the south, with Carroll and Montgomery counties to the east. The county seat is Frederick, a historic city known for its well-preserved architecture and Civil War history. Frederick County’s economy is diverse, with industries including agriculture, biotechnology, and manufacturing. The county is also a hub for commuters working in the Washington, D.C., and Baltimore metropolitan areas. Established in 1748, Frederick County has a rich history tied to colonial America, the Revolutionary War, and the Civil War.
County Facts
- Population: Approximately 280,000 (2023 estimate)
- County Seat: Frederick
- Major Airports: Frederick Municipal Airport
- Major Highways: I-70, I-270, US-15, US-40
2. Baltimore County
Overview
Baltimore County is located in northern Maryland, surrounding but not including Baltimore City. It is bordered by Harford County to the northeast and Carroll County to the west. The county seat is Towson, a large suburban area that serves as a major educational and retail hub. Baltimore County has a diverse economy, with key industries including healthcare, education, manufacturing, and finance. Its proximity to Baltimore City makes it a popular residential area for commuters. Baltimore County was established in 1659 and has a deep historical connection to the development of Maryland’s economy, particularly in the shipping and industrial sectors.
County Facts
- Population: Approximately 860,000 (2023 estimate)
- County Seat: Towson
- Major Airports: Baltimore/Washington International Thurgood Marshall Airport (nearby)
- Major Highways: I-83, I-95, I-695, I-70, I-795
3. Montgomery County
Overview
Montgomery County is located in the central part of Maryland, just northwest of Washington, D.C. It borders Frederick County to the north and Prince George’s County to the east. The county seat is Rockville, though Bethesda is another major hub. Montgomery County is one of the wealthiest counties in the United States and is home to a large number of federal government agencies, contractors, and research institutions, including the National Institutes of Health (NIH) and the Food and Drug Administration (FDA). Established in 1776, Montgomery County has grown into a key suburban area for Washington, D.C., with a highly educated population and a strong economy based on government, healthcare, and technology.
County Facts
- Population: Approximately 1.1 million (2023 estimate)
- County Seat: Rockville
- Major Airports: Ronald Reagan Washington National Airport (nearby), Dulles International Airport (nearby)
- Major Highways: I-495, I-270, US-29, MD-355
4. Prince George’s County
Overview
Prince George’s County is located in central Maryland, bordering Washington, D.C., to the west and Anne Arundel County to the east. The county seat is Upper Marlboro, though its most populous areas are closer to the Washington, D.C. metro area, including towns like Largo and College Park. The county’s economy is closely tied to federal government employment, education, and healthcare, with major institutions like NASA’s Goddard Space Flight Center and the University of Maryland located within its boundaries. Established in 1696, Prince George’s County has a rich history, with many historical landmarks and connections to colonial Maryland.
County Facts
- Population: Approximately 980,000 (2023 estimate)
- County Seat: Upper Marlboro
- Major Airports: Baltimore/Washington International Thurgood Marshall Airport (nearby)
- Major Highways: I-495, I-95, US-50, MD-4
5. Anne Arundel County
Overview
Anne Arundel County is located in central Maryland, bordered by the Chesapeake Bay to the east and Prince George’s County to the west. The county seat is Annapolis, the capital of Maryland and a historic city known for the U.S. Naval Academy. Anne Arundel County’s economy is driven by government, military, and maritime industries, with a significant presence of federal agencies and defense contractors, particularly near Fort Meade and the NSA. The county’s waterfront location makes it a popular destination for boating and tourism. Established in 1650, Anne Arundel County is named after Lady Anne Arundell, the wife of Lord Baltimore, and has a long maritime history.
County Facts
- Population: Approximately 590,000 (2023 estimate)
- County Seat: Annapolis
- Major Airports: Baltimore/Washington International Thurgood Marshall Airport
- Major Highways: I-97, I-695, US-50, MD-2
6. Harford County
Overview
Harford County is located in northeastern Maryland, bordering the Chesapeake Bay to the southeast and Pennsylvania to the north. The county seat is Bel Air, a town known for its historic charm and growing suburban developments. Harford County’s economy is diverse, with significant sectors in defense, manufacturing, and healthcare. Aberdeen Proving Ground, a major U.S. Army installation, is a key employer in the county. Harford County is known for its scenic landscapes, including the Susquehanna State Park and Havre de Grace’s waterfront. Established in 1773, the county has a rich history tied to the American Revolution and early industrial development.
County Facts
- Population: Approximately 260,000 (2023 estimate)
- County Seat: Bel Air
- Major Airports: Baltimore/Washington International Thurgood Marshall Airport (nearby)
- Major Highways: I-95, US-1, US-40
7. Washington County
Overview
Washington County is located in western Maryland, bordered by Pennsylvania to the north and West Virginia to the south, with the Potomac River serving as a natural boundary. The county seat is Hagerstown, which is a regional transportation and industrial hub. Washington County’s economy is driven by manufacturing, healthcare, and transportation, with the Hagerstown Regional Airport and access to major highways supporting logistics. The county has a rich Civil War history, with Antietam National Battlefield located nearby. Established in 1776, Washington County was named after George Washington and has deep historical ties to early American expansion and military conflict.
County Facts
- Population: Approximately 153,000 (2023 estimate)
- County Seat: Hagerstown
- Major Airports: Hagerstown Regional Airport
- Major Highways: I-70, I-81, US-11, US-40
8. Carroll County
Overview
Carroll County is located in northern Maryland, bordered by Pennsylvania to the north and Frederick County to the west. The county seat is Westminster, a town known for its historical buildings and vibrant downtown area. Carroll County is largely rural, with agriculture playing a significant role in the local economy, though it has seen increasing suburban growth due to its proximity to Baltimore and Washington, D.C. Established in 1837, Carroll County is named after Charles Carroll, a signer of the Declaration of Independence, and has a rich history rooted in farming and early American politics.
County Facts
- Population: Approximately 172,000 (2023 estimate)
- County Seat: Westminster
- Major Airports: Baltimore/Washington International Thurgood Marshall Airport (nearby)
- Major Highways: MD-140, MD-97, MD-27
9. Charles County
Overview
Charles County is located in southern Maryland, bordered by the Potomac River to the west and Prince George’s County to the north. The county seat is La Plata, though Waldorf is the largest population center and a major suburban community. Charles County’s economy is closely tied to federal government jobs, retail, and healthcare, with many residents commuting to Washington, D.C. The county also has a strong military presence due to the nearby Naval Surface Warfare Center in Indian Head. Established in 1658, Charles County was named after Charles I of England and has a long history of colonial settlements and agriculture.
County Facts
- Population: Approximately 170,000 (2023 estimate)
- County Seat: La Plata
- Major Airports: Ronald Reagan Washington National Airport (nearby)
- Major Highways: US-301, MD-5, MD-6
10. Wicomico County
Overview
Wicomico County is located on the eastern shore of Maryland, bordered by the Wicomico River to the west and Delaware to the north. The county seat is Salisbury, the largest city on the Eastern Shore and a regional hub for education, healthcare, and commerce. Wicomico County’s economy is diverse, with key sectors in poultry farming, manufacturing, and retail. The county is home to Salisbury University and the Perdue Farms headquarters, both of which are major employers. Established in 1867, Wicomico County is named after the Wicomico River, and its history is tied to the development of agriculture and trade along the Eastern Shore.
County Facts
- Population: Approximately 105,000 (2023 estimate)
- County Seat: Salisbury
- Major Airports: Salisbury-Ocean City Wicomico Regional Airport
- Major Highways: US-13, US-50