Yellowstone County Demographics

A map of Yellowstone County's Population by Race

Race	2024 Pop	2020 Pop	2024 %	2020 %
White	140,945	136,514	83.4%	82.9%
Hispanic	11,144	10,115	6.6%	6.1%
Multiracial	7,899	8,303	4.7%	5.0%
Native American/Other	7,009	7,333	4.1%	4.5%
Asian	1,203	1,279	0.7%	0.8%
Black	757	1,187	0.4%	0.7%

Yellowstone County, Montana has an estimated population of 168,957, a slight increase from the 164,731 recorded in the 2020 Census. The population is 83.4% White, 6.6% Hispanic, 4.7% Multiracial, 4.1% Native American/Other, 0.7% Asian, and 0.4% Black. This demographic dot map shows the population of Yellowstone County, with one dot drawn for each person counted by the Census, color-coded by race.

Yellowstone has become slightly less racially diverse since the 2020 Census. It is about as diverse as Montana overall. Demographers use a diversity index to measure the probability that two randomly selected individuals belong to different racial or ethnic groups. In Yellowstone County, that probability was 30.5% in 2020 and 29.6% in the most recent ACS estimates.

Yellowstone County is ranked the most populous county in Montana, out of 56 counties. Yellowstone County was ranked the 1st most populous county in the 2020 Census.

Yellowstone County's White Population

140,945 residents of Yellowstone County, or 83.4% of the population, identify as White. The share of White residents in Yellowstone County is comparable to the share in Montana overall, where 83.6% of the population is White. Yellowstone County ranks 45th statewide in terms of White residents as a share of the population, out of 56 counties.

Since the 2020 Census, Yellowstone County's White population has grown by an estimated 3.2%. White residents' share of Yellowstone County's population has increased from 82.9% to 83.4%.

Yellowstone County is more White than neighboring Big Horn County (27% White). Yellowstone County is less White than neighboring Musselshell County (86.6% White), Golden Valley County (90.3% White), Carbon County (90.1% White), and Treasure County (93% White).

Yellowstone County's Black Population

757 residents of Yellowstone County, or 0.4% of the population, identify as Black. The share of Black residents in Yellowstone County is comparable to the share in Montana overall, where 0.4% of the population is Black. Yellowstone County ranks 4th statewide in terms of Black residents as a share of the population, out of 56 counties.

Since the 2020 Census, Yellowstone County's Black population has declined by an estimated 36.2%. Black residents' share of Yellowstone County's population has remained roughly unchanged at 0.4%.

Yellowstone County is more Black than neighboring Musselshell County (0% Black), Big Horn County (0.3% Black), Carbon County (0.3% Black), and Treasure County (0% Black). Yellowstone County is less Black than neighboring Golden Valley County (0.8% Black).

Yellowstone County's Asian Population

1,203 residents of Yellowstone County, or 0.7% of the population, identify as Asian. The share of Asian residents in Yellowstone County is comparable to the share in Montana overall, where 0.8% of the population is Asian. Yellowstone County ranks 6th statewide in terms of Asian residents as a share of the population, out of 56 counties.

Since the 2020 Census, Yellowstone County's Asian population has declined by an estimated 5.9%. Asian residents' share of Yellowstone County's population has remained roughly unchanged at 0.7%.

Yellowstone County is more Asian than neighboring Musselshell County (0% Asian), Big Horn County (0.2% Asian), Golden Valley County (0% Asian), and Carbon County (0% Asian). Yellowstone County is less Asian than neighboring Treasure County (1% Asian).

Yellowstone County's Hispanic Population

11,144 residents of Yellowstone County, or 6.6% of the population, identify as Hispanic. The share of Hispanic residents in Yellowstone County is comparable to the share in Montana overall, where 4.6% of the population is Hispanic. Yellowstone County ranks 1st statewide in terms of Hispanic residents as a share of the population, out of 56 counties.

Since the 2020 Census, Yellowstone County's Hispanic population has grown by an estimated 10.2%. Hispanic residents' share of Yellowstone County's population has increased from 6.1% to 6.6%.

Yellowstone County is more Hispanic than neighboring Musselshell County (4.3% Hispanic), Big Horn County (4.7% Hispanic), Golden Valley County (4.3% Hispanic), Carbon County (3% Hispanic), and Treasure County (5.2% Hispanic).

Yellowstone County's Native American/Other Population

7,009 residents of Yellowstone County, or 4.1% of the population, identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other. The share of Native American/Other residents in Yellowstone County is comparable to the share in Montana overall, where 5.9% of the population is Native American/Other. Yellowstone County ranks 15th statewide in terms of Native American/Other residents as a share of the population, out of 56 counties.

Since the 2020 Census, Yellowstone County's Native American/Other population has declined by an estimated 4.4%. Native American/Other residents' share of Yellowstone County's population has remained roughly unchanged at 4.1%.

Yellowstone County is more Native American/Other than neighboring Golden Valley County (0.8% Native American/Other), Carbon County (2% Native American/Other), and Treasure County (0.1% Native American/Other). Yellowstone County is less Native American/Other than neighboring Musselshell County (5.8% Native American/Other), and Big Horn County (66.2% Native American/Other).

Yellowstone County's Multiracial Population

7,899 residents of Yellowstone County, or 4.7% of the population, identify as Multiracial. The share of Multiracial residents in Yellowstone County is comparable to the share in Montana overall, where 4.7% of the population is Multiracial. Yellowstone County ranks 15th statewide in terms of Multiracial residents as a share of the population, out of 56 counties.

Since the 2020 Census, Yellowstone County's Multiracial population has declined by an estimated 4.9%. Multiracial residents' share of Yellowstone County's population has remained roughly unchanged at 4.7%.

Yellowstone County is more Multiracial than neighboring Musselshell County (3.3% Multiracial), Big Horn County (1.6% Multiracial), Golden Valley County (3.8% Multiracial), Carbon County (4.5% Multiracial), and Treasure County (0.7% 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.