Marion County Demographics

A map of Marion County's Population by Race

Marion County, Missouri has an estimated population of 28,457, a less than 1% change from the 28,525 recorded in the 2020 Census. The population is 89.0% White, 4.2% Black, 3.5% Multiracial, 2.0% Hispanic, 0.8% Asian, and 0.5% Native American/Other. This demographic dot map shows the population of Marion County, with one dot drawn for each person counted by the Census, color-coded by race.

Marion has become less racially diverse since the 2020 Census. It is considerably less diverse than Missouri overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In Marion County, that probability was 23.1% in 2020 and 20.4% in the most recent ACS estimates.

Marion County is ranked the 39th most populous county in Missouri, out of 115 counties. Marion County was ranked the 39th most populous county in the 2020 Census.

Marion County's White Population

25,330 residents of Marion County, or 89.0% of the population, identify as White. The share of White residents in Marion County is considerably higher than in Missouri overall, where 76.3% of the population is White. Marion County ranks 79th statewide in terms of White residents as a share of the population, out of 115 counties.

Since the 2020 Census, Marion County's White population has grown by an estimated 1.6%. White residents' share of Marion County's population has increased from 87.4% to 89.0%.

Marion County is less White than neighboring Ralls County (92.8% White), Lewis County (91.5% White), Shelby County (93.6% White), Adams County (90% White), and Monroe County (91.6% White).

Marion County's Black Population

1,192 residents of Marion County, or 4.2% of the population, identify as Black. The share of Black residents in Marion County is lower than in Missouri overall, where 10.9% of the population is Black. Marion County ranks 26th statewide in terms of Black residents as a share of the population, out of 115 counties.

Since the 2020 Census, Marion County's Black population has declined by an estimated 12.5%. Black residents' share of Marion County's population has decreased from 4.8% to 4.2%.

Marion County is more Black than neighboring Ralls County (1.8% Black), Lewis County (3.9% Black), Shelby County (1.1% Black), Adams County (2.8% Black), and Monroe County (3.5% Black).

Marion County's Asian Population

228 residents of Marion County, or 0.8% of the population, identify as Asian. The share of Asian residents in Marion County is comparable to the share in Missouri overall, where 2.1% of the population is Asian. Marion County ranks 31st statewide in terms of Asian residents as a share of the population, out of 115 counties.

Since the 2020 Census, Marion County's Asian population has grown by an estimated 38.2%. Asian residents' share of Marion County's population has remained roughly unchanged at 0.8%.

Marion County is more Asian than neighboring Ralls County (0.2% Asian), Lewis County (0.5% Asian), Shelby County (0.4% Asian), Adams County (0.7% Asian), and Monroe County (0.4% Asian).

Marion County's Hispanic Population

582 residents of Marion County, or 2.0% of the population, identify as Hispanic. The share of Hispanic residents in Marion County is slightly lower than in Missouri overall, where 5.2% of the population is Hispanic. Marion County ranks 83rd statewide in terms of Hispanic residents as a share of the population, out of 115 counties.

Since the 2020 Census, Marion County's Hispanic population has grown by an estimated 12.8%. Hispanic residents' share of Marion County's population has remained roughly unchanged at 2.0%.

Marion County is more Hispanic than neighboring Ralls County (1.2% Hispanic), Lewis County (1.1% Hispanic), and Monroe County (1.8% Hispanic). Marion County is less Hispanic than neighboring Shelby County (2.3% Hispanic), and Adams County (2.1% Hispanic).

Marion County's Native American/Other Population

138 residents of Marion County, or 0.5% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Marion County is comparable to the share in Missouri overall, where 0.7% of the population is Native American/Other. Marion County ranks 66th statewide in terms of Native American/Other residents as a share of the population, out of 115 counties.

Since the 2020 Census, Marion County's Native American/Other population has declined by an estimated 22.9%. Native American/Other residents' share of Marion County's population has remained roughly unchanged at 0.5%.

Marion County is more Native American/Other than neighboring Ralls County (0.3% Native American/Other), Lewis County (0.1% Native American/Other), Shelby County (0.1% Native American/Other), and Adams County (0.3% Native American/Other). Marion County is less Native American/Other than neighboring Monroe County (0.8% Native American/Other).

Marion County's Multiracial Population

987 residents of Marion County, or 3.5% of the population, identify as Multiracial. The share of Multiracial residents in Marion County is comparable to the share in Missouri overall, where 4.8% of the population is Multiracial. Marion County ranks 48th statewide in terms of Multiracial residents as a share of the population, out of 115 counties.

Since the 2020 Census, Marion County's Multiracial population has declined by an estimated 28.1%. Multiracial residents' share of Marion County's population has decreased from 4.8% to 3.5%.

Marion County is more Multiracial than neighboring Lewis County (2.9% Multiracial), Shelby County (2.5% Multiracial), and Monroe County (1.8% Multiracial). Marion County is less Multiracial than neighboring Ralls County (3.7% Multiracial), and Adams County (4.1% Multiracial).

Sources: Most recent population estimates are from the 2020-2024 American Community Survey 5-Year Estimates. 2020 population counts and map data are from 2020 Census State Redistricting Data. Geographic data are from Census TIGER/Line Shapefiles.