Counties in Ohio by population

Franklin County had the highest population of 88 counties in 2020, at 1.32 million. Vinton County had the lowest, at 12,803. The median was 58,573 and the figure for Ohio was 11.8 million. Source: the U.S. Census Bureau.

Highest1,324,478Franklin County
Lowest12,803Vinton County
Median58,57388 counties
Ohio11,798,534History

Top 40 counties, 2020

CSVChart (SVG)

Franklin CountyFranklin County: 1,324,478 persons1,324,478Cuyahoga CountyCuyahoga County: 1,262,619 persons1,262,619Hamilton CountyHamilton County: 830,412 persons830,412Summit CountySummit County: 539,833 persons539,833Montgomery CountyMontgomery County: 537,115 persons537,115Lucas CountyLucas County: 430,831 persons430,831Butler CountyButler County: 390,845 persons390,845Stark CountyStark County: 374,476 persons374,476Lorain CountyLorain County: 313,514 persons313,514Warren CountyWarren County: 243,211 persons243,211Lake CountyLake County: 232,517 persons232,517Mahoning CountyMahoning County: 228,006 persons228,006Delaware CountyDelaware County: 215,181 persons215,181Clermont CountyClermont County: 208,751 persons208,751Trumbull CountyTrumbull County: 201,664 persons201,664Medina CountyMedina County: 182,636 persons182,636Licking CountyLicking County: 178,786 persons178,786Greene CountyGreene County: 168,141 persons168,141Portage CountyPortage County: 161,853 persons161,853Fairfield CountyFairfield County: 159,451 persons159,451Clark CountyClark County: 135,888 persons135,888Wood CountyWood County: 132,246 persons132,246Richland CountyRichland County: 124,969 persons124,969Wayne CountyWayne County: 116,899 persons116,899Miami CountyMiami County: 108,974 persons108,974Allen CountyAllen County: 102,116 persons102,116Columbiana CountyColumbiana County: 101,661 persons101,661Ashtabula CountyAshtabula County: 97,497 persons97,497Geauga CountyGeauga County: 95,383 persons95,383Tuscarawas CountyTuscarawas County: 93,205 persons93,205Muskingum CountyMuskingum County: 86,449 persons86,449Ross CountyRoss County: 77,067 persons77,067Erie CountyErie County: 75,471 persons75,471Hancock CountyHancock County: 74,939 persons74,939Scioto CountyScioto County: 73,849 persons73,849Belmont CountyBelmont County: 66,285 persons66,285Marion CountyMarion County: 65,385 persons65,385Jefferson CountyJefferson County: 65,159 persons65,159Union CountyUnion County: 63,069 persons63,069Knox CountyKnox County: 62,804 persons62,804
persons. Source: U.S. Census Bureau. Retrieved 2026-10-08.

Full ranking

RankCounties2020
persons
1Franklin County1,324,478
2Cuyahoga County1,262,619
3Hamilton County830,412
4Summit County539,833
5Montgomery County537,115
6Lucas County430,831
7Butler County390,845
8Stark County374,476
9Lorain County313,514
10Warren County243,211
11Lake County232,517
12Mahoning County228,006
13Delaware County215,181
14Clermont County208,751
15Trumbull County201,664
16Medina County182,636
17Licking County178,786
18Greene County168,141
19Portage County161,853
20Fairfield County159,451
21Clark County135,888
22Wood County132,246
23Richland County124,969
24Wayne County116,899
25Miami County108,974
26Allen County102,116
27Columbiana County101,661
28Ashtabula County97,497
29Geauga County95,383
30Tuscarawas County93,205
31Muskingum County86,449
32Ross County77,067
33Erie County75,471
34Hancock County74,939
35Scioto County73,849
36Belmont County66,285
37Marion County65,385
38Jefferson County65,159
39Union County63,069
40Knox County62,804
41Athens County62,386
42Washington County59,657
43Sandusky County58,880
44Pickaway County58,659
45Huron County58,487
46Lawrence County58,146
47Seneca County55,061
48Ashland County52,485
49Darke County51,901
50Shelby County48,158
51Auglaize County46,466
52Logan County46,117
53Holmes County44,239
54Madison County43,864
55Brown County43,684
56Highland County43,363
57Fulton County42,647
58Mercer County42,534
59Clinton County42,035
60Crawford County42,013
61Preble County41,007
62Ottawa County40,303
63Champaign County38,741
64Guernsey County38,426
65Defiance County38,268
66Williams County37,084
67Coshocton County36,590
68Perry County35,459
69Morrow County34,996
70Putnam County34,392
71Jackson County32,671
72Hardin County30,724
73Gallia County29,226
74Fayette County28,969
75Van Wert County28,922
76Hocking County28,040
77Henry County27,663
78Adams County27,451
79Pike County27,064
80Carroll County26,761
81Meigs County22,168
82Wyandot County21,878
83Paulding County18,809
84Harrison County14,498
85Noble County14,098
86Morgan County13,756
87Monroe County13,350
88Vinton County12,803

Other periods

About this ranking

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (PadrĂ³n). United States: Census Bureau population estimates for 1 July. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

For Denmark, Statistics Denmark counts the registered resident population on 1 January. Greenland and the Faroe Islands are excluded. The annual series selects the first-quarter reference date from FOLK1A. The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-08.

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Rank Counties in Ohio by population using official data, and cite the source.
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Questions

Which county has the highest population?

Franklin County, with 1.32 million in 2020, according to the U.S. Census Bureau.

Which county has the lowest population?

Vinton County, with 12,803 in 2020.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Annual estimates of the resident population for the United States, states and counties, 1 July (Population Estimates Program). Retrieved 2026-10-08.

Population: other rankings

Counties in Ohio: more rankings