Arnold, MO Demographics

A map of Arnold's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	18,451	18,511	88.0%	88.7%
Multiracial	1,413	1,182	6.7%	5.7%
Hispanic	548	636	2.6%	3.0%
Asian	380	232	1.8%	1.1%
Native American/Other	112	103	0.5%	0.5%
Black	52	194	0.2%	0.9%

Arnold, Missouri has an estimated population of 20,956, a less than 1% change from the 20,858 recorded in the 2020 Census. The population is 88.0% White, 6.7% Multiracial, 2.6% Hispanic, 1.8% Asian, 0.5% Native American/Other, and 0.2% Black. This demographic dot map shows the population of Arnold, with one dot drawn for each person counted by the Census, color-coded by race.

Arnold has become more 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 Arnold, that probability was 20.8% in 2020 and 21.9% in the most recent ACS estimates.

Arnold is ranked the 36th most populous place in Missouri, out of 1,082 places. This ranking is based on the Census definition of a place, which includes incorporated places like cities, towns, and villages, as well as unincorporated census-designated places (CDPs). Arnold was ranked the 36th most populous place in the 2020 Census.

Arnold's White Population

18,451 residents of Arnold, or 88.0% of the population, identify as White. The share of White residents in Arnold is considerably higher than in Missouri overall, where 76.3% of the population is White. Arnold ranks 615th statewide in terms of White residents as a share of the population, out of 1,082 places.

Since the 2020 Census, Arnold's White population has remained roughly the same. White residents' share of Arnold's population has decreased from 88.7% to 88.0%.

Arnold is more White than neighboring Imperial (87.3% White), and Mehlville (87.5% White). Arnold is less White than neighboring Oakville (88.5% White), Kimmswick (97.3% White), and Concord (91.4% White).

Arnold's Black Population

52 residents of Arnold, or 0.2% of the population, identify as Black. The share of Black residents in Arnold is considerably lower than in Missouri overall, where 10.9% of the population is Black. Arnold ranks 424th statewide in terms of Black residents as a share of the population, out of 1,082 places.

Since the 2020 Census, Arnold's Black population has declined by an estimated 73.2%. Black residents' share of Arnold's population has decreased from 0.9% to 0.2%.

Arnold is more Black than neighboring Kimmswick (0% Black). Arnold is less Black than neighboring Oakville (2.3% Black), Imperial (1.3% Black), Concord (1.2% Black), and Mehlville (5.4% Black).

Arnold's Asian Population

380 residents of Arnold, or 1.8% of the population, identify as Asian. The share of Asian residents in Arnold is comparable to the share in Missouri overall, where 2.1% of the population is Asian. Arnold ranks 173rd statewide in terms of Asian residents as a share of the population, out of 1,082 places.

Since the 2020 Census, Arnold's Asian population has grown by an estimated 63.8%. Asian residents' share of Arnold's population has increased from 1.1% to 1.8%.

Arnold is more Asian than neighboring Oakville (1.6% Asian), Imperial (0.3% Asian), and Kimmswick (0% Asian). Arnold is less Asian than neighboring Concord (2% Asian), and Mehlville (2.4% Asian).

Arnold's Hispanic Population

548 residents of Arnold, or 2.6% of the population, identify as Hispanic. The share of Hispanic residents in Arnold is slightly lower than in Missouri overall, where 5.2% of the population is Hispanic. Arnold ranks 376th statewide in terms of Hispanic residents as a share of the population, out of 1,082 places.

Since the 2020 Census, Arnold's Hispanic population has declined by an estimated 13.8%. Hispanic residents' share of Arnold's population has remained roughly unchanged at 2.6%.

Arnold is more Hispanic than neighboring Kimmswick (1.8% Hispanic), Concord (0.7% Hispanic), and Mehlville (1.9% Hispanic). Arnold is less Hispanic than neighboring Oakville (2.9% Hispanic), and Imperial (4.3% Hispanic).

Arnold's Native American/Other Population

112 residents of Arnold, 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 Arnold is comparable to the share in Missouri overall, where 0.7% of the population is Native American/Other. Arnold ranks 608th statewide in terms of Native American/Other residents as a share of the population, out of 1,082 places.

Since the 2020 Census, Arnold's Native American/Other population has grown by an estimated 8.7%. Native American/Other residents' share of Arnold's population has remained roughly unchanged at 0.5%.

Arnold is more Native American/Other than neighboring Oakville (0.1% Native American/Other), Imperial (0% Native American/Other), Kimmswick (0% Native American/Other), Concord (0% Native American/Other), and Mehlville (0.1% Native American/Other).

Arnold's Multiracial Population

1,413 residents of Arnold, or 6.7% of the population, identify as Multiracial. The share of Multiracial residents in Arnold is comparable to the share in Missouri overall, where 4.8% of the population is Multiracial. Arnold ranks 363rd statewide in terms of Multiracial residents as a share of the population, out of 1,082 places.

Since the 2020 Census, Arnold's Multiracial population has grown by an estimated 19.5%. Multiracial residents' share of Arnold's population has increased from 5.7% to 6.7%.

Arnold is more Multiracial than neighboring Oakville (4.6% Multiracial), Kimmswick (0.9% Multiracial), Concord (4.8% Multiracial), and Mehlville (2.6% Multiracial). Arnold is less Multiracial than neighboring Imperial (6.8% 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.