Monroe County Demographics

A map of Monroe County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	33,291	32,680	95.0%	93.5%
Hispanic	683	646	1.9%	1.8%
Multiracial	564	1,211	1.6%	3.5%
Asian	209	186	0.6%	0.5%
Black	207	118	0.6%	0.3%
Native American/Other	82	121	0.2%	0.3%

Monroe County, Illinois has an estimated population of 35,036, a less than 1% change from the 34,962 recorded in the 2020 Census. The population is 95.0% White, 1.9% Hispanic, 1.6% Multiracial, 0.6% Black, 0.6% Asian, and 0.2% Native American/Other. This demographic dot map shows the population of Monroe County, with one dot drawn for each person counted by the Census, color-coded by race.

Monroe has become less racially diverse since the 2020 Census. It is considerably less diverse than Illinois overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In Monroe County, that probability was 12.5% in 2020 and 9.6% in the most recent ACS estimates.

Monroe County is ranked the 40th most populous county in Illinois, out of 102 counties. Monroe County was ranked the 40th most populous county in the 2020 Census.

Monroe County's White Population

33,291 residents of Monroe County, or 95.0% of the population, identify as White. The share of White residents in Monroe County is significantly higher than in Illinois overall, where 58.1% of the population is White. Monroe County ranks 25th statewide in terms of White residents as a share of the population, out of 102 counties.

Since the 2020 Census, Monroe County's White population has grown by an estimated 1.9%. White residents' share of Monroe County's population has increased from 93.5% to 95.0%.

Monroe County is more White than neighboring St. Clair County (59.1% White), Jefferson County (88.5% White), St. Louis County (44.4% White), Ste. Genevieve County (93.8% White), and Randolph County (85.1% White).

Monroe County's Black Population

207 residents of Monroe County, or 0.6% of the population, identify as Black. The share of Black residents in Monroe County is considerably lower than in Illinois overall, where 13.3% of the population is Black. Monroe County ranks 92nd statewide in terms of Black residents as a share of the population, out of 102 counties.

Since the 2020 Census, Monroe County's Black population has grown by an estimated 75.4%. Black residents' share of Monroe County's population has remained roughly unchanged at 0.6%.

Monroe County is less Black than neighboring St. Clair County (27.7% Black), Jefferson County (1% Black), St. Louis County (42.1% Black), Ste. Genevieve County (1.2% Black), and Randolph County (8.2% Black).

Monroe County's Asian Population

209 residents of Monroe County, or 0.6% of the population, identify as Asian. The share of Asian residents in Monroe County is lower than in Illinois overall, where 5.9% of the population is Asian. Monroe County ranks 47th statewide in terms of Asian residents as a share of the population, out of 102 counties.

Since the 2020 Census, Monroe County's Asian population has grown by an estimated 12.4%. Asian residents' share of Monroe County's population has remained roughly unchanged at 0.6%.

Monroe County is more Asian than neighboring Ste. Genevieve County (0% Asian). Monroe County is less Asian than neighboring St. Clair County (1.6% Asian), Jefferson County (1% Asian), and St. Louis County (3.5% Asian).

Monroe County's Hispanic Population

683 residents of Monroe County, or 1.9% of the population, identify as Hispanic. The share of Hispanic residents in Monroe County is significantly lower than in Illinois overall, where 18.8% of the population is Hispanic. Monroe County ranks 73rd statewide in terms of Hispanic residents as a share of the population, out of 102 counties.

Since the 2020 Census, Monroe County's Hispanic population has grown by an estimated 5.7%. Hispanic residents' share of Monroe County's population has remained roughly unchanged at 1.9%.

Monroe County is more Hispanic than neighboring Ste. Genevieve County (1.5% Hispanic). Monroe County is less Hispanic than neighboring St. Clair County (5.1% Hispanic), Jefferson County (2.6% Hispanic), St. Louis County (5.3% Hispanic), and Randolph County (3.8% Hispanic).

Monroe County's Native American/Other Population

82 residents of Monroe County, or 0.2% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Monroe County is comparable to the share in Illinois overall, where 0.5% of the population is Native American/Other. Monroe County ranks 75th statewide in terms of Native American/Other residents as a share of the population, out of 102 counties.

Since the 2020 Census, Monroe County's Native American/Other population has declined by an estimated 32.2%. Native American/Other residents' share of Monroe County's population has remained roughly unchanged at 0.2%.

Monroe County is more Native American/Other than neighboring Ste. Genevieve County (0.1% Native American/Other). Monroe County is less Native American/Other than neighboring St. Clair County (0.7% Native American/Other), Jefferson County (0.4% Native American/Other), St. Louis County (0.6% Native American/Other), and Randolph County (0.4% Native American/Other).

Monroe County's Multiracial Population

564 residents of Monroe County, or 1.6% of the population, identify as Multiracial. The share of Multiracial residents in Monroe County is comparable to the share in Illinois overall, where 3.4% of the population is Multiracial. Monroe County ranks 45th statewide in terms of Multiracial residents as a share of the population, out of 102 counties.

Since the 2020 Census, Monroe County's Multiracial population has declined by an estimated 53.4%. Multiracial residents' share of Monroe County's population has decreased from 3.5% to 1.6%.

Monroe County is less Multiracial than neighboring St. Clair County (5.8% Multiracial), Jefferson County (6.5% Multiracial), St. Louis County (4% Multiracial), Ste. Genevieve County (3.3% Multiracial), and Randolph County (1.9% 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.