Ohio County Populations, 2020 Census
| wdt_ID | County | Population |
|---|---|---|
| 1 | Adams | 27,477 |
| 2 | Allen | 102,206 |
| 3 | Ashland | 52,447 |
| 4 | Astabula | 97,574 |
| 5 | Athens | 62,431 |
| 6 | Auglaize | 46,422 |
| 7 | Belmont | 66,497 |
| 8 | Brown | 43,676 |
| 9 | Butler | 390,357 |
| 10 | Carroll | 26,721 |
| 11 | Champaign | 38,714 |
| 12 | Clark | 136,001 |
| 13 | Clermont | 208,601 |
| 14 | Clinton | 42,018 |
| 15 | Columbiana | 101,877 |
| 16 | Coshocton | 36,612 |
| 17 | Crawford | 42,025 |
| 18 | Cuyahoga | 1,264,817 |
| 19 | Darke | 51,881 |
| 20 | Defiance | 38,286 |
| 21 | Delaware | 214,124 |
| 22 | Erie | 75,622 |
| 23 | Fairfield | 158,921 |
| 24 | Fayette | 28,951 |
| 25 | Franklin | 1,323,807 |
| 26 | Fulton | 42,713 |
| 27 | Gallia | 29,220 |
| 28 | Geauga | 95,397 |
| 29 | Greene | 167,966 |
| 30 | Guernsey | 38,438 |
| 31 | Hamilton | 830,639 |
| 32 | Hancock | 74,920 |
| 33 | Hardin | 30,696 |
| 34 | Harrison | 14,483 |
| 35 | Henry | 27,662 |
| 36 | Highland | 43,317 |
| 37 | Hocking | 28,050 |
| 38 | Holmes | 44,223 |
| 39 | Huron | 58,565 |
| 40 | Jackson | 32,653 |
| 41 | Jefferson | 65,249 |
| 42 | Knox | 62,721 |
| 43 | Lake | 232,603 |
| 44 | Lawrence | 58,240 |
| 45 | Licking | 178,519 |
| 46 | Logan | 46,150 |
| 47 | Lorain | 312,964 |
| 48 | Lucas | 431,279 |
| 49 | Madison | 43,824 |
| 50 | Mahoning | 228,614 |
| 51 | Marion | 65,359 |
| 52 | Medina | 182,470 |
| 53 | Meigs | 22,210 |
| 54 | Mercer | 42,528 |
| 55 | Miami | 108,774 |
| 56 | Monroe | 13,385 |
| 57 | Montgomery | 537,309 |
| 58 | Morgan | 13,802 |
| 59 | Morrow | 34,950 |
| 60 | Muskingum | 86,410 |
| 61 | Noble | 14,115 |
| 62 | Ottawa | 40,364 |
| 63 | Paulding | 18,806 |
| 64 | Perry | 35,408 |
| 65 | Pickaway | 58,539 |
| 66 | Pike | 27,088 |
| 67 | Portage | 161,791 |
| 68 | Preble | 40,999 |
| 69 | Putnam | 34,451 |
| 70 | Richland | 124,936 |
| 71 | Ross | 77,093 |
| 72 | Sandusky | 58,896 |
| 73 | Scioto | 74,008 |
| 74 | Seneca | 55,069 |
| 75 | Shelby | 48,230 |
| 76 | Stark | 374,853 |
| 77 | Summit | 540,428 |
| 78 | Trumbull | 201,977 |
| 79 | Tuscarawas | 93,263 |
| 80 | Union | 62,784 |
| 81 | Van Wert | 28,931 |
| 82 | Vinton | 12,800 |
| 83 | Warren | 242,337 |
| 84 | Washington | 59,771 |
| 85 | Wayne | 116,894 |
| 86 | Williams | 37,102 |
| 87 | Wood | 132,248 |
| 88 | Wyandot | 21,900 |
| County | Population |