Idaho local data guide

Fastest-Growing Demographic Groups in Idaho

Idaho's population growth remains robust, characterized by significant demographic shifts across age cohorts and ethnic groups. As of 2025, growth is heavily concentrated in urban centers, with specific age groups and minority populations driving the state's expanding demographic profile.

Updated with grounded research as of 2026-09-08.

The short answer

Between 2020 and 2025, Idaho's fastest-growing age cohort was the 70–79 age group, followed by the 40–49 and 20–29 cohorts. Simultaneously, the state's Hispanic population has emerged as a primary driver of growth, outpacing other groups in buying power expansion and increasing its total share of the state's demographic makeup.

Key facts

Fastest-Growing Age Cohorts (2020–2025)
The 70–79 age cohort experienced the highest growth, followed by the 40–49 and 20–29 age groups.
Ethnic Demographic Expansion
The Hispanic population has been a primary driver of growth in minority populations, leading in per capita buying power growth.
Urban Concentration of Growth
In 2025, 90% of Idaho's total population growth occurred within the state's urban counties (including Ada, Canyon, and Kootenai).

Age-Based Demographic Shifts

Idaho is experiencing notable diversification across its age demographics. The period between 2020 and 2025 highlighted significant expansion in the 70–79 age bracket, which saw the fastest growth. This trend suggests a strong influx of retirees or an aging-in-place effect in established communities. Concurrently, the 40–49 and 20–29 cohorts also expanded rapidly, pointing to a mix of workforce migration and family-stage households settling into the state.

Economic and Ethnic Trends

Growth in Idaho is not uniform across all groups. The Hispanic community, in particular, has consistently outpaced other groups in per capita buying power growth. This demographic segment is expanding its total share of the state's population, playing an increasingly vital role in Idaho's overall economic expansion and contributing to the state's evolving labor market and consumer base.

Geographic Distribution of Growth

While 80% of Idaho’s counties saw population increases in 2025, the vast majority of that growth is localized. Roughly 90% of the state’s total population growth in 2025 was concentrated within urban counties, specifically Ada, Canyon, Kootenai, Bonneville, and Twin Falls. These urban centers maintain a consistent annual growth rate of approximately 1.8%, significantly outpacing rural areas.

Common questions

Which counties are seeing the most population growth?

As of 2025, 90% of Idaho's total population growth is concentrated in the state's urban counties, including Ada, Canyon, Kootenai, Bonneville, and Twin Falls.

Are there specific age groups leading Idaho's growth?

Yes. According to 2020–2025 data, the 70–79 age cohort grew the fastest, with the 40–49 and 20–29 cohorts also showing strong growth trends.

Related Idaho questions

  • What are the fastest-growing cities in Idaho?
  • How does Idaho's age distribution compare to the national average?
  • Which counties in Idaho are experiencing the highest percentage growth?

Sources and verification