With 3,682 people, Lewis County is a county in Idaho. The median age is 49.0, about 10 years above the US median. Four-year degrees are less common here than nationally, at 21% of adults. Density works out to 8 people per square mile. 1% of locals were born outside the United States. That trails the Idaho median by roughly 34%.
At a glance
Lower income
median household income $51,615, below the US median
US median: $82,259
Older
median age 49.0
US median: 38.9
Less educated
21% hold a bachelor's degree
US average: 36%
Less affordable
home values up 58%, inflation adjusted
US median home: $376,019
Unique to this place
What stands out about Lewis County
What changed most since 1990
Median home value (2024 dollars)$91,923 → $225,300(+145%)US over the same years: +67%
Median age36.5 → 49.0(+12.5 years)US over the same years: +6.0 years
Adults with a bachelor's degree13.2% → 21.3%(+8.1 pts)US over the same years: +15.3 pts
Shares are "alone or in combination": a person with both Medicare and Medicaid counts in each, so categories overlap and do not sum to 100%.
Section 09 · Service history
Veterans
Veterans by period of service, 2024
Gulf War (2001 or later)12.5%(39)
US avg: 26.4%
Gulf War (1990s)10%(31)
US avg: 24.3%
Vietnam era47.9%(149)
US avg: 33.1%
Korean War5.1%(16)
US avg: 4.5%
World War II0%(0)
US avg: 1%
Share of the 311 veterans here. A veteran who served across eras counts in each, so shares can total more than 100%. Peacetime-only service is included in the total but not shown as an era.
BAR + DOT: THIS PLACE · TICK: US AVERAGE
Over time
Lewis County, decade by decade
Lewis County population, inflation-adjusted income and home value, education, and diversity by year
Year
Population
Median household income
Median home value
Bachelor's degree+
Diversity score
1990
3,516
$50,224
$91,923
13.2%
16.7
2000
3,747
$57,224
$142,453
14.8%
20.0
2010
3,821
$51,512
$161,264
15.5%
25.4
2020
3,533
$51,354
$181,806
19.1%
31.1
2024
3,682
$51,615
$225,300
21.3%
39.6
Census years come from the decennial census and the latest year from the American Community Survey, so part of any change between those two rows can reflect the different surveys. Dollar figures are adjusted for inflation to 2024 dollars; a figure ending in "+" was at the Census Bureau's reporting cap that year. The diversity score runs from 0 to 100; see how it's calculated.
