Ohio county map

How Ohio’s counties are laid out

Ohio’s 88 counties cover 44,826 square miles, so the average county is about 510 square miles, roughly 20 miles across — the 19th-century standard that let a farmer reach the courthouse and return in a day. The 11,799,448 people counted in 2020 are concentrated in the “three Cs” and their suburbs: Franklin (Columbus), Cuyahoga (Cleveland) and Hamilton (Cincinnati) together hold about a quarter of the state, and the ring of counties around them — Delaware, Lake, Lorain, Summit, Butler, Warren, Clermont — another large share. The rural counties of the north-west are flat corn and soybean land; those of the south-east are the hills of the Appalachian Plateau and the least populated part of the state.

Washington County, seat Marietta, was created in 1788 as the first county of the Northwest Territory and covered roughly the eastern half of what is now Ohio. Hamilton (1790) was the second, and the rest of the map filled in between statehood in 1803 and the 1820s as the Congress Lands, Virginia Military District, Connecticut Western Reserve and other survey tracts were settled. The Western Reserve in the north-east explains the New England-style names there — Portage, Geauga, Trumbull, Ashtabula — while the counties of the north-west, the last to be organised after the Black Swamp was drained, carry names like Paulding, Van Wert, Defiance and Putnam from 1820 onward.

Ohio counties are governed by three elected commissioners plus separately elected officials (auditor, treasurer, sheriff, recorder, engineer); only Summit and Cuyahoga counties have adopted charter governments with a county executive and council. The whole state is on Eastern Time.

All 88 counties of Ohio

Five county facts

• Largest by area: Ashtabula County, seat Jefferson, about 700 square miles of land in the north-east corner on Lake Erie and the Pennsylvania line. Licking, Ross, Darke, Muskingum and Washington counties are each around 640–690 square miles.
• Smallest by area: Lake County, seat Painesville, about 230 square miles of land squeezed between Cleveland and the lakeshore. Ottawa, Hamilton and Summit counties are also under 420 square miles.
• Most populous: Franklin County, with about 1,324,000 people in 2020, passing Cuyahoga County (about 1,264,000) for the first time. Hamilton County (Cincinnati) is third at about 830,000, followed by Summit (Akron) and Montgomery (Dayton).
• Least populous: Vinton County, seat McArthur, with about 12,800 people in the forested hills south-east of Columbus. Noble, Monroe, Morgan, Harrison and Paulding counties are the only others under 20,000.
• Oldest and newest: Washington County (1788) is the oldest, followed by Hamilton (1790). Noble County, formed in 1851 from parts of Guernsey, Monroe, Morgan and Washington, is the newest. Ohio has no independent cities.

Reading the map

Press Streets and zoom in on the highlighted state to see county lines. The Ohio River forms the entire southern and south-eastern border, and Columbiana, Jefferson, Belmont, Monroe, Washington, Meigs, Gallia, Lawrence, Scioto, Adams, Brown, Clermont and Hamilton counties all front it, from East Liverpool to Cincinnati. Lake Erie bounds Ashtabula, Lake, Cuyahoga, Lorain, Erie, Sandusky, Ottawa and Lucas (Toledo) counties on the north; Ottawa County includes the Lake Erie islands. The Scioto River runs from Hardin County south through Columbus and Chillicothe to Portsmouth; the Muskingum drains the eastern hills to Marietta; the Great Miami crosses Dayton and Hamilton to the Ohio. Fayette County’s seat, Washington Court House, has the longest name of any Ohio county seat.

Related maps

• Ohio map — cities, borders and geography.
• Blank Ohio map and printable Ohio map.
• Columbus, the state capital and largest city, in Franklin County; Cleveland in Cuyahoga County.
• Neighbouring county maps: Michigan, Pennsylvania, West Virginia, Kentucky, Indiana.
• East North Central division · the Midwest · Great Lakes region · Eastern Time Zone.
• Geography: Ohio River, Great Lakes, Appalachian Mountains.
• All US county maps.