Adams County is a county in Ohio, United States, about 55 miles southeast of Cincinnati. It had a population of 27,477 at the 2020 census, an estimated 27,865 by 2025, and covers 584 square miles (1,510 km2) centred near 38°50′N 83°29′W.
West Union is the county seat and the county’s largest village; its postal code is 45693. The county holds 6 incorporated villages and 29 unincorporated communities across 15 townships, and it runs on Eastern Time. Its FIPS code is 39001.
Towns & Villages in Adams County
Adams County has 35 named places on record: 6 incorporated villages — every one classified a village under Ohio law, since none reaches the 5,000-resident threshold for city status — and 29 unincorporated communities with no local government of their own. Unincorp. covers crossroads and rural communities with no formal boundary.
| Place | Type | Township | Pop. | ZIP |
|---|---|---|---|---|
| West Union | Village · seat | Tiffin | 3,004 | 45693 |
| Manchester | Village | Manchester | 1,839 | 45144 |
| Peebles | Village | Meigs | 1,774 | 45660 |
| Winchester | Village | Winchester | 987 | 45697 |
| Seaman | Village | Scott | 973 | 45679 |
| Rome (Stout) | Village | Green | 83 | 45684 |
| Cherry Fork | Unincorp. | Wayne | — | — |
| Blue Creek | Unincorp. | Jefferson | — | — |
| Bentonville | Unincorp. | Sprigg | — | — |
| Lynx | Unincorp. | Brush Creek | — | — |
| Tulip | Unincorp. | Brush Creek | — | — |
| Selig | Unincorp. | Brush Creek | — | — |
| Beasley Fork | Unincorp. | — | — | — |
| Bradysville | Unincorp. | — | — | — |
| Cedar Mills | Unincorp. | — | — | — |
| Dunkinsville | Unincorp. | — | — | — |
| Eckmansville | Unincorp. | — | — | — |
| Fairview | Unincorp. | — | — | — |
| Harshaville | Unincorp. | — | — | — |
| Jacksonville | Unincorp. | — | — | — |
| Jaybird | Unincorp. | — | — | — |
| Locust Grove | Unincorp. | — | — | — |
| Louden | Unincorp. | — | — | — |
| Louisville | Unincorp. | — | — | — |
| Marble Furnace | Unincorp. | — | — | — |
| May Hill | Unincorp. | — | — | — |
| Mineral Springs | Unincorp. | — | — | — |
| Rockville | Unincorp. | — | — | — |
| Sandy Springs | Unincorp. | — | — | — |
| Steam Furnace | Unincorp. | — | — | — |
| Tranquility | Unincorp. | — | — | — |
| Unity | Unincorp. | — | — | — |
| Wamsley | Unincorp. | — | — | — |
| Wrightsville | Unincorp. | — | — | — |
| Youngsville | Unincorp. | — | — | — |
Two pairs of names on this list are easy to confuse. Rome and Stout are the same village on the Ohio River in Green Township — the post office there has operated under the name Stout since the community’s early years, so the two names refer to one place, not two. And this Winchester, in western Winchester Township, is one of five Ohio villages sharing the name; a separate Winchester sits in Brown County to the west and another in Jackson County to the east.
Townships
Adams County’s 15 civil townships, by population at the 2020 census:
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Tiffin | 5,210 | West Union (seat) |
| Meigs | 3,761 | Peebles |
| Scott | 2,262 | Seaman (most of) |
| Winchester | 2,190 | Winchester |
| Liberty | 2,065 | West Union (small portion) |
| Manchester | 1,882 | Manchester |
| Sprigg | 1,744 | Bentonville, a corner of Manchester |
| Bratton | 1,380 | — |
| Wayne | 1,363 | Cherry Fork, part of Seaman |
| Oliver | 1,352 | — |
| Brush Creek | 1,097 | Lynx, Tulip, Selig |
| Franklin | 1,097 | — |
| Jefferson | 898 | Blue Creek |
| Monroe | 624 | — |
| Green | 552 | Rome (Stout) |
ZIP Codes
- 45693 — West Union (the county seat’s ZIP)
- 45144 — Manchester
- 45660 — Peebles
- 45697 — Winchester
- 45679 — Seaman
- 45684 — Rome, delivered under the post office name Stout
The county’s 29 unincorporated communities have no post office or ZIP code of their own; mail there is delivered under the nearest incorporated village’s code above.
Geography
Adams County sits in Ohio’s unglaciated Appalachian foothills, a hillier belt than most of the state that escaped the last ice age’s flattening effect. Of its 584 square miles, 582 are land and 2.4 are water, about 0.4 percent — the county has no large reservoir, and Ohio Brush Creek, which runs the length of the county before reaching the Ohio River, accounts for most of its surface water. The Ohio River itself forms the county’s entire southern boundary, separating it from Kentucky.
Highland County lies to the north, Pike County to the northeast, Scioto County to the east, and Brown County to the west. Across the Ohio River to the south are Lewis County and, further southwest, Mason County, both in Kentucky. Highland County, Pike County, Scioto County, Brown County, Lewis County and Mason County all border Adams County directly.
Demographics
Adams County had a population of 27,477 at the 2020 census, and the latest estimate puts the county near 27,865 residents by 2025. West Union and Manchester are the two largest communities, together holding roughly 4,800 of the county’s residents. Median household income runs $50,264 (2023 ACS), well below Ohio’s statewide figure of $67,769 (2023 ACS). Population density works out to roughly 47 people per square mile of land, among the lowest in Ohio, reflecting the county’s rural, hilly terrain and its distance from any metropolitan core.
Economy & Local Life
Health care and social assistance employs the most workers in the county, about 1,926 people, followed by manufacturing at 1,593 and retail trade at 1,477, out of roughly 10,436 total employed residents. The Adams County Regional Medical Center, built in Seaman in 2007, is the county’s principal hospital and one of its largest employers. Educational services, real estate and construction pay the highest median wages locally, though most county jobs sit in lower-paying retail and health-support roles. A 2019 statewide economic report identified Adams County as the poorest county in Ohio by household income, with the state’s highest unemployment rate that year — a standing condition of the local economy rather than a recent shift.
History
The Northwest Territory’s governor created Adams County on 10 July 1797, one of the region’s earliest counties, more than five years before Ohio became a state. It was named for John Adams, then serving as the young nation’s second president. West Union was laid out as the county seat in 1803 and has held the courthouse ever since; a post office has operated there continuously since 1805.
The county’s best-known landmark predates its founding by more than two thousand years. Near Peebles, on a plateau above Ohio Brush Creek, the Adena culture built the 1,348-foot Serpent Mound around 300 BCE, the largest serpent-shaped effigy earthwork known anywhere in the world; the Fort Ancient culture appears to have repaired or rebuilt sections of it around 900 CE. The site sits atop a meteorite-impact crater and was designated a National Historic Landmark in 1966; the Ohio History Connection operates a museum and observation tower there today.
Getting There
No interstate highway crosses Adams County. State Routes 41, 125 and 247 intersect and run concurrently through downtown West Union; US Route 52 follows the Ohio River through Manchester; and State Route 32, the Appalachian Highway, passes near Seaman and Winchester on its way toward Cincinnati.
- Cincinnati — about 55 miles southwest
- Chillicothe — about 48 miles northeast
- Portsmouth — about 30 miles east
- Hillsboro — about 28 miles north
Cincinnati/Northern Kentucky International Airport, roughly 63 miles northwest of West Union, is the nearest major commercial airport. No Amtrak line reaches Adams County; the closest station is Cincinnati Union Terminal, served by the Cardinal.
Frequently Asked Questions
Where is Adams County located?
It sits in Ohio’s unglaciated Appalachian foothills along the Ohio River, about 55 miles southeast of Cincinnati, bordered by Highland, Pike, Scioto and Brown counties and by Kentucky across the river.
What is the population of Adams County?
27,477 at the 2020 census, with an estimate near 27,865 by 2025.
How big is Adams County?
584 square miles (1,510 km2), of which 582 square miles are land.
What is the county seat of Adams County?
West Union, laid out in 1803, is the county seat and the county’s largest village.
How many towns and villages are in Adams County?
Six incorporated villages — West Union, Manchester, Peebles, Winchester, Seaman and Rome (Stout) — plus 29 unincorporated communities such as Blue Creek, Cherry Fork and Locust Grove.
What ZIP codes does Adams County use?
45693 for West Union, 45144 for Manchester, 45660 for Peebles, 45697 for Winchester, 45679 for Seaman and 45684 for Rome (Stout).
What is Adams County known for?
Serpent Mound, a 1,348-foot Adena effigy earthwork near Peebles built around 300 BCE, the largest serpent-shaped mound known anywhere.
More counties in this state: Towns and villages in Ohio.