Boulder

County:: Jefferson County
County Seat:: Yes
Area (mi²):: 1.124
State:: Montana

Boulder is a city located in Jefferson County, Montana. Boulder has a 2025 population of 1,334. It is also the county seat of Jefferson County. Boulder is currently growing at a rate of 1.99% annually and its population has increased by 10.61% since the most recent census, which recorded a population of 1,206 in 2020.

The average household income in Boulder is $79,712 with a poverty rate of 8.72%.The median age in Boulder is 40.8 years: 41.1 years for males, and 37.9 years for females.

Demographics

The racial composition of Boulder includes 92.99% White, 4.22% Native American, and smaller percentages for other race, Two or more races and multiracial populations.

Population by Race

Race	Population	Percentage (of total)
White	1,233	92.99%
Native American	56	4.22%
Other race	19	1.43%
Two or more races	18	1.36%

Boulder Marital Status

Married

Widowed

Divorced

Separated

Never Married

Economics and Income Statistics

Boulder's average per capita income is $37,955. Household income levels show a median of $61,250. The poverty rate stands at 8.72%.

Families: A family includes the owner or renter of the home along with everyone related to them - whether through birth, marriage, or adoption. This includes relatives like spouses, children, parents, siblings, grandparents, and any other family members.

Households: A household includes all the people who occupy a housing unit (such as a house or apartment) as their usual place of residence.

Non Families: A nonfamily household is either someone living alone or when the owner/renter lives with people they aren't related to, like roommates.

Name	Median	Mean
Married Families	$100,781	-
Families	$64,375	$99,866
Households	$61,250	$79,712
Non Families	$40,789	$44,321

$37,955

Average Income

$61,250

Median Household Income

8.72%

Poverty Rate