St. Louis County Demographics

A map of St. Louis County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	128,219	129,368	44.4%	42.9%
Black	121,473	128,993	42.1%	42.8%
Hispanic	15,297	15,405	5.3%	5.1%
Multiracial	11,564	13,132	4.0%	4.4%
Asian	10,146	12,205	3.5%	4.0%
Native American/Other	1,813	2,475	0.6%	0.8%

St. Louis County, Missouri has an estimated population of 288,512, a decrease from the 301,578 recorded in the 2020 Census. The population is 44.4% White, 42.1% Black, 5.3% Hispanic, 4.0% Multiracial, 3.5% Asian, and 0.6% Native American/Other. This demographic dot map shows the population of St. Louis County, with one dot drawn for each person counted by the Census, color-coded by race.

St. Louis has become slightly less racially diverse since the 2020 Census. It is considerably more 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 St. Louis County, that probability was 62.7% in 2020 and 62.0% in the most recent ACS estimates.

St. Louis County is ranked the 5th most populous county in Missouri, out of 115 counties. St. Louis County was ranked the 4th most populous county in the 2020 Census.

St. Louis County's White Population

128,219 residents of St. Louis County, or 44.4% of the population, identify as White. The share of White residents in St. Louis County is significantly lower than in Missouri overall, where 76.3% of the population is White. St. Louis County ranks 115th statewide in terms of White residents as a share of the population, out of 115 counties.

Since the 2020 Census, St. Louis County's White population has remained roughly the same. White residents' share of St. Louis County's population has increased from 42.9% to 44.4%.

St. Louis County is less White than neighboring St. Louis County (61.4% White), St. Clair County (59.1% White), Monroe County (95% White), Madison County (81.8% White), and St. Charles County (83% White).

St. Louis County's Black Population

121,473 residents of St. Louis County, or 42.1% of the population, identify as Black. The share of Black residents in St. Louis County is significantly higher than in Missouri overall, where 10.9% of the population is Black. St. Louis County ranks 1st statewide in terms of Black residents as a share of the population, out of 115 counties.

Since the 2020 Census, St. Louis County's Black population has declined by an estimated 5.8%. Black residents' share of St. Louis County's population has decreased from 42.8% to 42.1%.

St. Louis County is more Black than neighboring St. Louis County (24% Black), St. Clair County (27.7% Black), Monroe County (0.6% Black), Madison County (7.7% Black), and St. Charles County (5% Black).

St. Louis County's Asian Population

10,146 residents of St. Louis County, or 3.5% of the population, identify as Asian. The share of Asian residents in St. Louis County is comparable to the share in Missouri overall, where 2.1% of the population is Asian. St. Louis County ranks 3rd statewide in terms of Asian residents as a share of the population, out of 115 counties.

Since the 2020 Census, St. Louis County's Asian population has declined by an estimated 16.9%. Asian residents' share of St. Louis County's population has decreased from 4.0% to 3.5%.

St. Louis County is more Asian than neighboring St. Clair County (1.6% Asian), Monroe County (0.6% Asian), Madison County (0.8% Asian), and St. Charles County (3% Asian). St. Louis County is less Asian than neighboring St. Louis County (4.9% Asian).

St. Louis County's Hispanic Population

15,297 residents of St. Louis County, or 5.3% of the population, identify as Hispanic. The share of Hispanic residents in St. Louis County is comparable to the share in Missouri overall, where 5.2% of the population is Hispanic. St. Louis County ranks 18th statewide in terms of Hispanic residents as a share of the population, out of 115 counties.

Since the 2020 Census, St. Louis County's Hispanic population has remained roughly the same. Hispanic residents' share of St. Louis County's population has remained roughly unchanged at 5.3%.

St. Louis County is more Hispanic than neighboring St. Louis County (3.9% Hispanic), St. Clair County (5.1% Hispanic), Monroe County (1.9% Hispanic), Madison County (4.3% Hispanic), and St. Charles County (4.2% Hispanic).

St. Louis County's Native American/Other Population

1,813 residents of St. Louis County, or 0.6% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in St. Louis County is comparable to the share in Missouri overall, where 0.7% of the population is Native American/Other. St. Louis County ranks 34th statewide in terms of Native American/Other residents as a share of the population, out of 115 counties.

Since the 2020 Census, St. Louis County's Native American/Other population has declined by an estimated 26.7%. Native American/Other residents' share of St. Louis County's population has remained roughly unchanged at 0.6%.

St. Louis County is more Native American/Other than neighboring Monroe County (0.2% Native American/Other), Madison County (0.3% Native American/Other), and St. Charles County (0.5% Native American/Other). St. Louis County is less Native American/Other than neighboring St. Clair County (0.7% Native American/Other).

St. Louis County's Multiracial Population

11,564 residents of St. Louis County, or 4.0% of the population, identify as Multiracial. The share of Multiracial residents in St. Louis County is comparable to the share in Missouri overall, where 4.8% of the population is Multiracial. St. Louis County ranks 67th statewide in terms of Multiracial residents as a share of the population, out of 115 counties.

Since the 2020 Census, St. Louis County's Multiracial population has declined by an estimated 11.9%. Multiracial residents' share of St. Louis County's population has remained roughly unchanged at 4.0%.

St. Louis County is more Multiracial than neighboring Monroe County (1.6% Multiracial). St. Louis County is less Multiracial than neighboring St. Louis County (5.3% Multiracial), St. Clair County (5.8% Multiracial), Madison County (5% Multiracial), and St. Charles County (4.3% 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.