With 11,756,058 residents (2022 estimate), Ohio is the seventh-most populous state in the United States. It may not hold that spot for very much longer, though. Georgia is currently the eighth-most populous state, but it is growing at a faster rate than Ohio. In fact, many of Ohio’s counties are declining in population. There are, however, some counties in the Buckeye State that are booming. Here is a look at the ten fastest-growing counties in Ohio, along with some notable trends in the state’s shifting population.
Because population trends are best measured over a number of years rather than through momentary snapshots, this list is based on the growth each county experienced from the 2010 census to the most recent population estimates available from 2022. The counties are ranked based on the number of people added to the population in these twelve years.

10. Clermont County
- 2022 Population: 210,805
- Population Change from 2010: +13,442
- 14th Largest County in Ohio
- Fun Fact: Clermont County is the birthplace of Civil War General and U.S. President, Ulysses S. Grant.

Clermont County is home to Point Pleasant, the birthplace of Ulysses S. Grant.
©Photo by Greg Hume at en.wikipedia / CC BY 2.5, via Wikimedia Commons – License
9. Union County
- 2022 Population: 66,898
- Population Change from 2010: +14,598
- 39th Largest County in Ohio
- Fun Fact: Union County is a thriving agricultural hub. Around 70% of the county’s land is farmland.

Union County Ohio Court House is in the 39th largest county in Ohio.
©Emkamau / CC BY-SA 4.0, via Wikimedia Commons – License
8. Licking County
- 2022 Population: 181,359
- Population Change from 2010: +14,867
- 17th Largest County in Ohio
- Fun Fact: The Hopewell indigenous people built many earthworks prior to the arrival of European settlers. Most were destroyed, but remnants remain at the Great Circle Earthworks, Octagon Earthworks, and Wright Earthworks in Licking County.

Licking County is home to the remnants of earthworks built by the Hopewell Indians.
©Niagara66 / CC BY-SA 4.0 – License
7. Lorain County
- 2022 Population: 316,268
- Population Change from 2010: +14,912
- 9th Largest County in Ohio
- Fun Fact: Lorain is known as “The International City” because the city is home to more than 70 different nationalities.

The city of Lorain in Lorain County is located about 25 miles west of Cleveland.
©Alexander Wooledge / CC BY-SA 4.0, via Wikimedia Commons – License
6. Fairfield County
- 2022 Population: 162,898
- Population Change from 2010: +16,742
- 20th Largest County in Ohio
- Fun Fact: Lancaster, the Fairfield County Seat, was the birthplace of Civil War General, William Tecumseh Sherman.

Lake Loretta in Fairfield County’s Alley Park features the George Hutchins Covered Bridge.
©Kenneth Keifer/Shutterstock.com
5. Butler County
- 2022 Population: 388,420
- Population Change from 2010: +20,290
- 7th Largest County in Ohio
- Fun Fact: Butler County is home to Miami University. Founded in 1809, Miami is the second-oldest university in Ohio behind Ohio University, founded in 1804.

The historic bell tower on Miami University’s campus in Oxford, Ohio
©EEJCC / CC BY-SA 4.0, via Wikimedia Commons – License
4. Hamilton County
- 2022 Population: 825,037
- Population Change from 2010: +22,663
- 3rd Largest County in Ohio
- Fun Fact: Hamilton County is home to Cincinnati, the third-largest city in Ohio. The county was named after Alexander Hamilton, the nation’s first Secretary of the Treasury.

Cincinnati is the largest city in Hamilton County and the third-largest city in Ohio.
©Sean Pavone/Shutterstock.com
3. Warren County
- 2022 Population: 249,778
- Population Change from 2010: +37,085
- 10th Largest County in Ohio
- Fun Fact: Warren County is known as “Ohio’s Largest Playground” thanks in part to the presence of the Kings Island amusement park and many other attractions and events. The county is named for Joseph Warren, the Revolutionary War Soldier who sent Paul Revere on his famous midnight ride.

Warren County is home to the Kings Island amusement park.
©Fritzmann2002 / CC BY-SA 4.0, via Wikimedia Commons – License
2. Delaware County
- 2022 Population: 226,296
- Population Change from 2010: +52,082
- 13th Largest County in Ohio
- Fun Fact: Delaware County was the birthplace and home of President Rutherford B. Hayes. The county was named after the Delaware Indian tribe.

University Hall, Ohio Wesleyan University — Delaware, Ohio
©Christopher L. Riley / CC BY-SA 4.0, via Wikimedia Commons – License
1. Franklin County
- 2022 Population: 1,321,820
- Population Change from 2010: +158,406
- Ohio’s Largest County
- Fun Fact: Franklin County is home to Columbus, Ohio’s capital and the state’s largest city. The county was named after Benjamin Franklin.

Columbus, Ohio’s capital city, is located in Franklin County.
©Sean Pavone/Shutterstock.com
Notes and Trends
All 10 of Ohio’s fastest-growing counties are near the state’s three largest cities: Columbus, Cleveland, and Cincinnati.
- Lorain County borders Cuyahoga County, where Cleveland is located.
- Butler, Clermont, and Warren counties each border Hamilton County, where Cincinnati is found.
- Delaware, Fairfield, Licking, and Union counties all border Franklin County, where Columbus is located.
- And, of course, Hamilton and Franklin counties themselves are on the list with their major cities leading the population boom.
One interesting note is that while a bordering county experienced significant growth in the twelve-year period, Cuyahoga County itself saw a sharp population decline. In fact, Cuyahoga experienced the greatest population decline of any county in the state from 2010 to 2022. Cuyahoga County lost 44,077 people from 2010 to 2022. Despite that, it is still the second-most populous county in the state. Cuyahoga and Franklin counties are the only Ohio counties with populations over one million. Still, the trend for Cuyahoga County’s population is sharply downward.

The population of Cleveland, and Cuyahoga County as a whole, is dropping.
©iStock.com/Ralph Navarro
Biggest Percentage of Growth
Union County grew by a higher percentage relative to its 2010 population than any other county in the state. The 2010 population was 52,300, and the 2022 headcount was 66,898. That is a nearly 28% population increase during the twelve-year span.
Colleges and Universities
One major factor for county growth seen across the nation is the university effect. Counties that house colleges and universities tend to see some of the most aggressive growth. This trend is reflected in the Buckeye State.
- Franklin County is home to The Ohio State University.
- Delaware County houses Ohio Wesleyan University.
- Hamilton County is where the University of Cincinnati is found.
- Butler County is home to Miami University.

The Ohio State University is a major contributor to Franklin County’s explosive growth.
©Minh Nguyen / CC BY-SA 4.0 – License
Immigrating to Ohio
Ohio’s fastest-growing counties owe a portion of their increase to people who choose to immigrate to the state. According to Stacker, these are the top five nations represented in Ohio’s immigrant population.
- India – 64,344 residents
- Mexico – 44,019 residents
- China – 35,939 residents
- Republic of the Philippines – 17,244 residents
- Canada – 14,456 residents.
Least Populous County
We’ve seen the largest and fastest-growing counties in Ohio. Vinton County lies on the other side of the spectrum. It is the least-populous county in the state, with a 2022 population of 12,565 people. The county dropped from 13,435 in the 2010 census. Vinton County doesn’t have a lot of people, but it is home to Zaleski State Forest, the second-largest state forest in Ohio. It is also home to the famous Moonville Tunnel.

Vinton County, the least-populous county in the state, is home to Ohio’s second-largest state forest.
©DanaK~WaterPenny / CC BY 2.0 – License
Natural Decrease
Nationwide, the U.S. Census Bureau estimates that 73% of all counties in the United States experienced a “natural decrease” in population in 2021. The Census Bureau identifies a natural decrease “when there are more deaths than births in a population over a given time period.”
The rate of natural decrease rose significantly from the previous two years. Only 45.5% of U.S. counties experienced a natural decrease in 2019, and 55.5% saw a natural decrease in 2020. The reasons were varied, but fewer births, an aging population, and the COVID-19 pandemic were all major players in these results.
In Ohio, 55 counties saw a population decline from 2010. Some of those declines are attributed to a more transient population, but much can also be credited to natural decline.
Summary of 10 Fastest-Growing Counties in Ohio
Here’s a recap of the top 10 Ohio counties where the population is growing at the fastest rate.
Rank | County | 2022 Population | Population Change From 2010 |
---|---|---|---|
1 | Franklin County | 1,321,820 | +158,406 |
2 | Delaware County | 226,296 | +52,082 |
3 | Warren County | 249,778 | +37,085 |
4 | Hamilton County | 825,037 | +22,663 |
5 | Butler County | 388,420 | +20,290 |
6 | Fairfield County | 162,898 | +16,742 |
7 | Lorain County | 316,268 | +14,912 |
8 | Licking County | 181,359 | +14,867 |
9 | Union County | 66,898 | +14,598 |
10 | Clermont County | 210,805 | +13,442 |
The photo featured at the top of this post is © iStock.com/TraceRouda
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