Population of Counties in Indiana (2020)

The most populous county located in the state of Indiana is Marion County, home of Indianapolis, which, as of 2019, has a population of 954,670. Since the time that the last census was taken in 2010, Marion County has seen an increase in the total population of 5.35%. The next most populous counties in the state of Indiana after Marion County are Lake County (484,411), Allen County (375,351), and Hamilton County (330,086). Of these counties, only Lake County experienced a decline, dropping 2.32% in population. Hamilton County had the most significant growth with a growth rate of 19.38% since the 2010 census.

Indiana Counties with the Fewest Residents

The county with the lowest population in the state of Indiana is Ohio County, which has a population of 5,844. Since the last census in 2010, Ohio County’s population has seen a decrease of 4.12%. Following Ohio County are Union County (7,047), Warren County (8,263), and Benton County (8,653). All of these counties experienced a decline in the number of residents.

Indiana Counties with Rapid Growth

The county with the most rapid population growth was Hamilton County, home of Noblesville, which grew 19.38% to 330,086. Following Hamilton County is Boone County which grew 17.72% and Hendericks County with a population growth rate of 14.46%. The counties with the most significant population loss are Union County (-6.63%), Blackford County (-6.59%), and Pulaski County (-6.43%).

Name 2020 Population Growth Since 2010
Marion County954,6705.53%
Lake County484,411-2.32%
Allen County375,3515.45%
Hamilton County330,08619.38%
St. Joseph County270,7711.48%
Elkhart County205,5604.11%
Tippecanoe County193,04811.52%
Vanderburgh County180,9740.63%
Porter County169,5943.10%
Hendricks County167,00914.46%
Johnson County156,22511.37%
Monroe County146,9176.03%
Madison County129,641-1.50%
Clark County117,3606.14%
Delaware County114,772-2.45%
LaPorte County110,007-1.30%
Vigo County107,386-0.46%
Bartholomew County82,7537.72%
Howard County82,366-0.47%
Kosciusko County79,3442.59%
Floyd County77,7814.11%
Hancock County76,3518.72%
Morgan County70,1161.39%
Boone County66,99917.72%
Wayne County65,936-4.29%
Grant County65,936-5.68%
Warrick County62,5674.56%
Dearborn County49,568-1.04%
Henry County48,271-2.54%
Noble County47,5320.16%
Marshall County46,248-1.60%
Lawrence County45,668-0.94%
Shelby County44,5930.63%
Jackson County44,1113.58%
DeKalb County43,2262.17%
Dubois County42,5651.57%
Harrison County40,3502.60%
LaGrange County39,3305.85%
Montgomery County38,3460.65%
Cass County37,955-2.63%
Putnam County37,779-0.36%
Knox County36,895-3.90%
Huntington County36,240-2.36%
Adams County35,6363.44%
Miami County35,567-3.38%
Steuben County34,5861.32%
Whitley County34,0742.15%
Gibson County33,452-0.28%
Jasper County33,370-0.38%
Daviess County33,1474.50%
Clinton County32,250-2.92%
Jefferson County32,208-0.60%
Greene County32,006-3.61%
Wabash County31,280-4.77%
Ripley County28,523-1.02%
Wells County28,2061.90%
Washington County27,943-1.26%
Jennings County27,611-3.06%
Decatur County26,7943.86%
Clay County26,170-2.54%
Posey County25,540-1.23%
Randolph County24,851-5.07%
White County24,133-2.24%
Scott County23,878-1.18%
Fayette County23,047-5.26%
Starke County22,935-1.76%
Franklin County22,736-1.39%
Owen County20,845-3.36%
Jay County20,764-1.95%
Sullivan County20,690-3.27%
Spencer County20,327-2.80%
Carroll County20,127-0.33%
Fulton County20,092-3.46%
Orange County19,489-1.60%
Perry County19,102-1.59%
Parke County16,927-2.05%
Rush County16,663-4.15%
Fountain County16,351-5.35%
Vermillion County15,479-3.95%
Brown County15,2340.18%
Tipton County15,128-4.72%
Newton County14,011-1.57%
Pulaski County12,469-6.43%
Pike County12,410-2.51%
Blackford County11,930-6.59%
Switzerland County10,7170.20%
Crawford County10,558-1.42%
Martin County10,217-1.37%
Benton County8,653-2.37%
Warren County8,263-3.03%
Union County7,037-6.63%
Ohio County5,844-4.12%