Ohio Counties by Population (2025)
2025 Pop.
100K
200K
300K
400K
500K
600K
700K
800K
900K
1M
1.1M
1.2M
1.3M
Top 5 Most Populous Counties
1,373,703
1,242,509
843,159
539,721
539,573
88 Counties
| County | 2025 Pop. ↓ | Area (mi²) | Density | Change (2020) |
|---|---|---|---|---|
| Franklin County | 1,373,703 | 532 | 2,582 | 3.71% |
| Cuyahoga County | 1,242,509 | 457 | 2,719 | -1.59% |
| Hamilton County | 843,159 | 405 | 2,082 | 1.53% |
| Summit County | 539,721 | 413 | 1,307 | -0.02% |
| Montgomery County | 539,573 | 461 | 1,170 | 0.45% |
| Lucas County | 426,342 | 340 | 1,254 | -1.05% |
| Butler County | 403,491 | 467 | 864 | 3.22% |
| Stark County | 375,130 | 575 | 652 | 0.15% |
| Lorain County | 324,897 | 491 | 662 | 3.62% |
| Warren County | 258,539 | 401 | 645 | 6.29% |
| Delaware County | 243,200 | 443 | 549 | 13.03% |
| Lake County | 232,756 | 229 | 1,016 | 0.1% |
| Mahoning County | 225,584 | 411 | 549 | -1.07% |
| Clermont County | 216,044 | 453 | 477 | 3.49% |
| Trumbull County | 200,246 | 618 | 324 | -0.71% |
| Licking County | 186,256 | 682 | 273 | 4.17% |
| Medina County | 185,135 | 421 | 440 | 1.37% |
| Greene County | 174,359 | 414 | 421 | 3.7% |
| Fairfield County | 169,894 | 504 | 337 | 6.54% |
| Portage County | 164,603 | 487 | 338 | 1.7% |
| Clark County | 135,235 | 396 | 342 | -0.48% |
| Wood County | 133,341 | 617 | 216 | 0.81% |
| Richland County | 124,703 | 495 | 252 | -0.23% |
| Wayne County | 116,629 | 555 | 210 | -0.23% |
| Miami County | 113,002 | 407 | 278 | 3.71% |
| Allen County | 100,881 | 403 | 250 | -1.23% |
| Columbiana County | 99,509 | 532 | 187 | -2.11% |
| Ashtabula County | 96,850 | 702 | 138 | -0.68% |
| Geauga County | 95,335 | 400 | 238 | -0.05% |
| Tuscarawas County | 92,079 | 568 | 162 | -1.2% |
| Muskingum County | 86,852 | 665 | 131 | 0.45% |
| Ross County | 75,752 | 689 | 110 | -1.71% |
| Hancock County | 75,185 | 531 | 142 | 0.36% |
| Union County | 73,677 | 432 | 171 | 16.78% |
| Erie County | 73,557 | 251 | 293 | -2.55% |
| Scioto County | 71,420 | 610 | 117 | -3.29% |
| Marion County | 65,124 | 404 | 161 | -0.41% |
| Belmont County | 64,404 | 532 | 121 | -2.85% |
| Knox County | 64,352 | 525 | 123 | 2.48% |
| Jefferson County | 63,684 | 408 | 156 | -2.3% |
| Athens County | 63,467 | 504 | 126 | 1.74% |
| Pickaway County | 63,252 | 501 | 126 | 7.82% |
| Sandusky County | 58,947 | 408 | 144 | 0.12% |
| Washington County | 58,151 | 632 | 92 | -2.52% |
| Huron County | 58,078 | 492 | 118 | -0.71% |
| Lawrence County | 55,520 | 453 | 123 | -4.51% |
| Seneca County | 54,832 | 551 | 100 | -0.41% |
| Ashland County | 52,657 | 423 | 124 | 0.34% |
| Darke County | 51,492 | 598 | 86 | -0.78% |
| Shelby County | 48,119 | 408 | 118 | -0.07% |
| Madison County | 46,394 | 467 | 99 | 5.78% |
| Logan County | 46,125 | 459 | 100 | 0.02% |
| Auglaize County | 45,826 | 401 | 114 | -1.39% |
| Holmes County | 44,897 | 423 | 106 | 1.49% |
| Brown County | 44,750 | 490 | 91 | 2.44% |
| Highland County | 43,982 | 553 | 80 | 1.43% |
| Mercer County | 42,848 | 462 | 93 | 0.74% |
| Fulton County | 42,105 | 405 | 104 | -1.25% |
| Clinton County | 42,066 | 409 | 103 | 0.07% |
| Crawford County | 41,661 | 402 | 104 | -0.84% |
| Preble County | 41,039 | 424 | 97 | 0.06% |
| Ottawa County | 39,565 | 255 | 155 | -1.82% |
| Champaign County | 38,957 | 429 | 91 | 0.55% |
| Defiance County | 38,851 | 411 | 95 | 1.53% |
| Guernsey County | 38,312 | 522 | 73 | -0.28% |
| Coshocton County | 37,140 | 564 | 66 | 1.49% |
| Williams County | 36,542 | 421 | 87 | -1.46% |
| Morrow County | 36,271 | 406 | 89 | 3.68% |
| Perry County | 35,787 | 408 | 88 | 0.94% |
| Putnam County | 34,158 | 483 | 71 | -0.72% |
| Jackson County | 32,777 | 420 | 78 | 0.32% |
| Hardin County | 30,398 | 470 | 65 | -1.05% |
| Van Wert County | 29,049 | 409 | 71 | 0.45% |
| Gallia County | 28,808 | 467 | 62 | -1.48% |
| Fayette County | 28,733 | 406 | 71 | -0.85% |
| Adams County | 27,800 | 584 | 48 | 1.27% |
| Henry County | 27,527 | 416 | 66 | -0.52% |
| Hocking County | 27,291 | 421 | 65 | -2.69% |
| Pike County | 27,147 | 440 | 62 | 0.26% |
| Carroll County | 26,166 | 395 | 66 | -2.01% |
| Wyandot County | 21,322 | 407 | 52 | -2.48% |
| Meigs County | 21,210 | 430 | 49 | -4.29% |
| Paulding County | 18,782 | 416 | 45 | -0.13% |
| Noble County | 14,193 | 398 | 36 | 0.61% |
| Harrison County | 13,901 | 402 | 35 | -4.08% |
| Morgan County | 13,438 | 416 | 32 | -2.28% |
| Monroe County | 12,937 | 456 | 28 | -3.14% |
| Vinton County | 12,592 | 412 | 31 | -1.69% |
Overview of Ohio Counties
There are 88 counties in Ohio.
Franklin County is the largest county in the state, with a population of 1,373,703. The most recent census shows that its population has increased by 0.04% since the previous census.
A number of other Ohio counties also boast relatively large populations for their state, though not able to match the density of Franklin County:
- Cuyahoga County : 1,242,509
- Hamilton County : 843,159
Ohio Counties with the Fewest Residents
The smallest county in Ohio is Vinton County , with a population of just 12,592. This total represents a decrease of 0.0% since the last census count was performed.
Other small counties include:
- Monroe County : 12,937
- Morgan County : 13,438
- Harrison County : 13,901
Ohio Counties with Rapid Growth
Union County , with its current population of 73,677, has shown the largest population growth, with an increase of 0.2% since the last census.
Franklin County has also had relatively high population growth of 0.04% with 1,373,703 residents.
On the other hand, Lawrence County has had the largest decrease in population, with its 55,520 current residents totalling 0.0% less than the previous census.
Sources
- US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
- US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
- American Community Survey (2009 - 2013)
- Census QuickFacts
- Historical Populations of States and Counties (1790 - 1990)