Hardin County, Ohio

Hardin County is a county in Ohio, United States, in the west-central part of the state, roughly halfway between Lima and Marion. It had a population of 30,696 at the 2020 census and covers 471 square miles (1,220 km2) centred near 40°40′N 83°40′W.

Kenton is the county seat, and its postal code is 43326. The county has one city, eight villages, one census-designated place, 15 civil townships, and a scatter of smaller unincorporated communities. Hardin County sits in the Eastern time zone.

Towns & Villages in Hardin County

Hardin County’s population centers are small: one city and eight villages, plus the unincorporated Dola census-designated place and a handful of crossroads communities. Kenton, the seat, is the only place with a population over 10,000; the rest are all under 1,000 residents.

Ada, in the county’s northeast corner, is Hardin County’s largest place by daytime population thanks to Ohio Northern University, though its year-round resident count trails Kenton. Several named crossroads — Foraker, Grant, Grassy Point, Hepburn, Holden, Huntersville, Jumbo, Jump, Maysville, Mentzer, Pfeiffer, Silver Creek and Yelverton — appear on county maps but have no population figures or ZIP codes of their own; they are served by the nearest listed post office town.

Townships

Hardin County is divided into 15 civil townships. Individual 2020 township population figures were not verified for this profile, so populations are omitted rather than estimated.

ZIP Codes

• 43326 — Kenton
• 45810 — Ada
• 45843 — Forest
• 45812 — Alger
• 43340 — Mount Victory
• 45836 — Dunkirk
• 43345 — Ridgeway
• 45835 — Dola
• 45859 — McGuffey (PO Box delivery only)
• 43346 — Roundhead (PO Box delivery only)

Patterson has no ZIP code of its own; mail there is generally addressed to the nearest listed post office town.

Geography

Hardin County lies on gently rolling farmland at the edge of the till plains of west-central Ohio, drained mainly by the Scioto River, which rises in the county’s Roundhead Township, and by tributaries of the Blanchard River in the north. The county’s total area is 471 square miles (1,220 km2), of which about 470 square miles (1,200 km2) is land and roughly 0.2 square miles (0.1%) is water.

Hardin County borders seven other Ohio counties: Hancock County to the north, Wyandot County to the northeast, Marion County to the east, Union County to the southeast, Logan County to the south, Auglaize County to the southwest, and Allen County to the northwest.

Demographics

The 2020 census counted 30,696 residents in Hardin County. Kenton and Ada are the county’s two largest communities; Kenton is the commercial and government center, while Ada’s population is heavily shaped by Ohio Northern University’s student body. Median household income in the county runs below the Ohio median of $67,769, consistent with its largely agricultural tax base. Population density is roughly 65 people per square mile, well under the statewide average.

Economy & Local Life

Agriculture, mainly corn and soybeans, remains the backbone of Hardin County’s economy, alongside grain processing and light manufacturing centered on Kenton. Ada is a distinct local economy of its own, anchored by Ohio Northern University, a private university that is the county’s largest single employer and draws students and staff from well beyond the county line. The Hardin County Fair, held each summer in Kenton, is the county’s best-known annual event.

History

Hardin County was created by the Ohio legislature on March 1, 1820, and formally organized in 1833 once its population justified independent county government. It is named for John Hardin, a colonel who served under Anthony Wayne in the Northwest Indian War and was killed in 1792 while carrying a peace message to the Miami people — a death commemorated in several Ohio and Kentucky place names, not only this county. Kenton, the seat, takes its own name from frontiersman Simon Kenton.

Getting There

U.S. Route 68 runs north–south through the county via Kenton, linking it to Findlay and Bellefontaine; several Ohio state routes cross it east–west. Approximate distances from Kenton:

• Findlay — 25 miles north
• Lima — 25 miles west
• Marion — 25 miles east
• Bellefontaine — 20 miles south

The nearest sizeable commercial airport is Rickenbacker International/John Glenn Columbus International, roughly 75 miles southeast; smaller general-aviation fields serve Kenton and Ada directly.

Frequently Asked Questions

Where is Hardin County, Ohio?
It is in west-central Ohio, bordered by Hancock, Wyandot, Marion, Union, Logan, Auglaize and Allen counties.

What is the population of Hardin County?
Hardin County had a population of 30,696 at the 2020 census.

How big is Hardin County?
The county covers 471 square miles (1,220 km2), almost all of it land.

What is the county seat of Hardin County?
Kenton is the county seat and largest city.

How many towns and villages are in Hardin County?
One city (Kenton), eight villages, one census-designated place (Dola), and several unincorporated crossroads communities.

What ZIP codes are in Hardin County?
Ten ZIP codes serve the county, including 43326 (Kenton), 45810 (Ada) and 45843 (Forest); the full list is above.

Why is Ada, Ohio well known despite its small size?
Ada is home to Ohio Northern University, a private university whose student population and staff make Ada a significant local center out of proportion to its year-round resident count.

More counties in this state: Towns and villages in Ohio.