Jefferson County, Idaho Demographics 2026

Name: Jefferson County, Idaho Demographics
Creator: U.S. Census Bureau
License: https://www.census.gov/data/developers/about/terms-of-service.html

Jefferson County, Idaho has a population of 33,154, the 12th most populous county in Idaho. The median household income is $86,679 and the median home value is $408,400. The poverty rate is 9.7%.

Data vintage: U.S. Census Bureau ACS 2020–2024 5-Year Estimates · refreshed July 2026 · Methodology & source notes

Jefferson County Quick Facts

Population 33,154

Median Household Income $86,679

Median Home Value $408,400

Poverty Rate 9.7%

Unemployment Rate 2.7%

Median Age 32.8 years

Homeownership Rate 83.0%

Affordability Ratio 4.7x

Bachelor's Degree+ 27.4%

High School Graduation 93.3%

Cities/Places 6

Population 33,154 12th of 44

Median Income $86,679 11% higher than state

Poverty Rate 9.7%

Unemployment 2.7%

How Jefferson County Changed

Change from the 2019–2023 ACS period to 2020–2024. These are rolling five-year estimates, not year-over-year measurements.

Metric	2019–2023	2020–2024	Change
Population	32,234	33,154	+2.9%
Median household income	$82,952	$86,679	+4.5%
Median home value	$335,000	$408,400	+21.9%

Median Household Income

Jefferson

$86,679

$77,800

National

$80,734

Median Home Value

Jefferson

$408,400

$418,600

National

$332,700

Economy & Housing

Household Income Distribution

Under $25K 10.3%

$25K-$50K 14.4%

$50K-$100K 36.2%

$100K+ 39.1%

Detailed income brackets

Under $10K

3.3%

$10K-$15K

2.7%

$15K-$20K

1.9%

$20K-$25K

2.4%

$25K-$30K

1.1%

$30K-$35K

4.7%

$35K-$40K

2.1%

$40K-$45K

2.3%

$45K-$50K

4.2%

$50K-$60K

6.7%

$60K-$75K

9.7%

$75K-$100K

19.8%

$100K-$125K

11.6%

$125K-$150K

10.0%

$150K-$200K

9.2%

$200K+

8.2%

Employment

2.7% Unemployment Rate State: 3.7%|National: 5.2%

66.1% Labor Force Participation

Housing Overview

Owner 83.0%

Renter 17.0%

Affordability Index Moderate

4.7x home value to income ratio

Median gross rent $1,138/mo 15.8% of median household income annually

People & Demographics

Age Distribution

Under 18

32.4%

18-34

20.0%

35-54

25.4%

55-74

18.0%

75+

4.3%

Race & Ethnicity

Diversity Index

Low Diversity

A less diverse community where one racial or ethnic group represents a large majority.

State average: 36 | National average: 61

Education

Educational Attainment (Adults 25+)

Cities & Places in Jefferson County

City	Population	Median Income	Poverty	Home Value
Rigby	5,404	$85,056	9.7%	$336,200
Menan	876	$80,833	6.9%	$292,700
Roberts	609	$62,188	14.8%	$258,300
Mud Lake	491	$69,167	14.3%	$171,600
Lewisville	453	$83,750	9.3%	$236,500
Hamer	59	$84,167	8.5%	$242,900

Explore Idaho Rankings

Cities by Population All cities ranked by size Richest Cities Ranked by median income Most Educated By bachelor's degree rate Most Affordable By housing affordability

Population Overview

Jefferson County is located in Idaho with a total population of 33,154. It is the 12th most populous county out of 44 in Idaho. The county encompasses 6 Census-designated places.

Age Demographics

The median age in Jefferson County is 32.8 years. This is 12% lower than the state median of 37.3 years. With 32.4% of the population under 18, Jefferson County has a notably young demographic profile, suggesting a family-oriented community.

Economy, Income & Housing

The median household income in Jefferson County is $86,679. This is 11% higher than the state median of $77,800. It is also 7% higher than the national median of $80,734. The poverty rate stands at 9.7%. This is 9% lower than the state poverty rate of 10.6%. The unemployment rate is 2.7%. This is 28% lower than the state rate of 3.7%. The median home value is $408,400. Housing costs are 2% lower than the state median of $418,600. The home-value-to-income ratio is 4.7x. 83.0% of occupied housing units are owner-occupied. This homeownership rate is 15% higher than the state average of 72.1%.

Race & Ethnicity

Jefferson County has a predominantly White (non-Hispanic) population, comprising 85.7% of all residents. Hispanic or Latino residents account for 11.0%. The Black or African American population (0.1%) is well below the state average of 0.7%. The Asian population (0.1%) is well below the state average of 1.3%.

Education

27.4% of residents aged 25 and older hold a bachelor's degree or higher. This is 14% lower than the state rate of 31.8%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 93.3%.

Data Sources & Methodology

All figures for Jefferson County come from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates, with comparisons drawn against Idaho and national averages from the same dataset. See our methodology page for how each metric is defined, or data.census.gov for official tables with margins of error.

Frequently Asked Questions

What is the population of Jefferson County, Idaho?

Jefferson County has a population of 33,154, making it the 12th most populous county in Idaho.

What is the median income in Jefferson County?

The median household income in Jefferson County is $86,679 with a poverty rate of 9.7%.

How many cities are in Jefferson County, Idaho?

Jefferson County contains 6 Census-designated places.