U.S. Population by Sex and Age 2026 — How Many People Are in America?

U.S. Population 2026 — ~343 Million Americans

The United States population in 2026 is approximately 343 million people — based on the Census Bureau's Vintage 2025 estimate of 341.8 million as of July 1, 2025, growing at approximately 0.5% annually. The U.S. is the world's 3rd most populous country, behind India (~1.45 billion) and China (~1.41 billion), and home to approximately 4.2% of the global population.

The most critical demographic story of 2026 is America's rapid ageing. The population aged 65 and older has reached 61.2 million — growing 3.1% in a single year (2023–2024) and 13% from 2020–2024. This is the fastest growth of any age group. Meanwhile, the under-18 population has declined to 73.1 million, falling 0.2% from 2023–2024 and 1.7% from 2020–2024. The gap between children and seniors has narrowed from over 20 million in 2020 to under 12 million in 2024 — and is on track to close entirely. The U.S. population and economic dynamics connect to our world GDP analysis.

How Many People Are in the U.S. in 2026?

The exact U.S. population in 2026 depends on the source and methodology. The U.S. Census Bureau — the official authority — reported 341,784,857 people as of July 1, 2025 (Vintage 2025 estimates). The UN World Population Prospects 2024 Revision estimates the U.S. mid-2026 population at approximately 349,035,494 — higher because the UN includes U.S. armed forces stationed abroad and uses a different demographic model.

For practical purposes, the U.S. population in 2026 is between 342 and 349 million, with most domestic planning figures using the Census Bureau's approximately 343 million estimate. The U.S. reached 300 million on October 17, 2006, and 330 million in April 2020. It is projected to reach 355 million by 2040 and 364 million by 2060. The U.S. grew by approximately 1.8 million (0.5%) between 2024 and 2025 — a slower rate than 2024's 0.98% growth, primarily due to reduced international immigration.

U.S. Total Population Growth — 2000 to 2026 (Millions)

How Many Adults Are in the U.S.? — ~276.8 Million (18+)

There are approximately 276.8 million adults aged 18 and older in the United States in 2026, representing approximately 80.5% of the total population. This figure includes all residents aged 18+ — from young adults just entering the workforce through the oldest centenarians. The adult population has grown significantly: in 2000, there were approximately 209 million adults in the U.S. — meaning the adult population has expanded by approximately 68 million people over 26 years, driven by population growth, immigration, and the aging of younger cohorts into adulthood.

Within the adult population, the young adult cohort (18–24) numbers approximately 30.4 million (8.9% of total). These are Americans who entered adulthood during or after the COVID-19 pandemic — a generation shaped by remote learning, record student debt, and one of the toughest entry-level housing markets in history. The prime earner cohort (25–44) at approximately 88.9 million represents the economic core of America — the age group with the highest rates of homeownership formation, consumer spending, and career advancement. The late-career cohort (45–64) at approximately 86.6 million includes the tail end of the baby boomers and Generation X, many approaching retirement planning decisions that will shape Social Security and investment markets for decades.

Breaking adults down further: Working-age adults (18–64) number approximately 205.7 million, representing 60.5% of the total U.S. population — the largest single age segment. Seniors (65+) number approximately 61.2 million (18.0%). Of those seniors, approximately 13.4 million are aged 85 and older — the fastest-growing sub-group at 4.2% annual growth. The adult share of U.S. population connects to labour force trends tracked in our U.S. financial markets analysis.

U.S. Population by Broad Age Group — Share 2026

U.S. population by age group 2026 (BusinessStats Research · Census Bureau Vintage 2024): Total ~343M · Adults (18+): ~276.8M (80.5%) · Working age 18-64: 205.7M (60.5%) · Seniors 65+: 61.2M (18.0%) · Children under 18: 73.1M (21.5%) · 85+: 13.4M (fastest growing, +4.2%/yr) · Median age: 39.1 years (record) · Largest age group: 31-40 years (~47M) · 11 states now have more seniors than children. Source: U.S. Census Bureau Vintage 2024 Population Estimates · June 2025.

U.S. Population by Age Group — Detailed Breakdown 2026

The largest single age group in America in 2026 is people in their 30s — approximately 47 million Americans aged 31–40. This reflects the large millennial generation (born approximately 1981–1996) now entering their prime working and family-forming years. The 25–44 age bracket contains approximately 88.9 million people (26.2% of the U.S. population) and experienced 0.8% growth from 2020–2024.

The school-age population (5–17 years) numbers approximately 53.3 million (15.7% of Americans) — showing a slight decline that impacts school enrollment planning across the country. Children under 5 number approximately 18.9 million — reflecting the continued drop in the U.S. fertility rate (now 1.6 children per woman, down from 2.1 in 2007). The 45–64 age group (late baby boomers and Generation X) stands at approximately 86.6 million (25.4%). Most dramatically, the 65–84 group grew 2.8% and the 85+ group grew an extraordinary 4.2% in 2023–2024 alone.

U.S. Population by Detailed Age Group — 2026

U.S. Population by Sex and Age Group — Males vs Females

Across every age group under approximately 50, American men slightly outnumber women — reflecting the biological birth sex ratio of approximately 104.7 boys per 100 girls. This male advantage persists through childhood (37.6 million boys vs 35.5 million girls under 18) and all through young adulthood. In the prime working-age bracket (25–44), the split is nearly equal: approximately 44.7 million men vs 44.2 million women. From age 50 onward, women begin to outnumber men, and this female advantage grows dramatically with age — driven by women's longer average life expectancy of 81.4 years versus men's 76.5 years.

At ages 65–69, there are approximately 9.0 million men vs 9.9 million women. By ages 75–79, the gap is 4.7M men vs 5.7M women. Among Americans aged 85+, only approximately 2.4 million men remain compared to 4.2 million women — meaning at the oldest ages, women outnumber men by nearly 2:1. Among the very oldest Americans (91+), women number approximately 1.3 million compared to only 0.7 million men. The U.S. male median age is 38.5 years while the female median age is 39.8 years — women skew slightly older due to their longevity advantage. The gender demographic connects to our U.S. gender demographics analysis.

U.S. Male vs Female Population by Age Group — 2026

U.S. Population by Age Group — Full Data Table 2026

The regional variation in U.S. age demographics is striking. The Northeast has the oldest median age at 40.6 years, driven by states like Maine, Vermont, and New Hampshire where young people have been leaving for decades. The West (38.4) and South (38.8) are America's youngest regions — reflecting higher birth rates, strong immigration, and in-migration of younger workers to Sunbelt metros like Dallas, Houston, Phoenix, Atlanta, and Miami. The Midwest sits at 39.3 years. At the state level, Maine has the oldest population (median age ~46) while Utah is the youngest (~31), reflecting Utah's higher-than-average fertility rate among its predominantly Mormon population. The age distribution by metro area is tracked in our U.S. metropolitan areas population analysis.

The trend toward an older American population has profound economic and social implications. The ratio of working-age adults to seniors is declining: from over 5 workers per retiree in 2000 to approximately 3.9 today, and projected to fall to approximately 2.5 by 2060 as the 85+ group continues its explosive growth. The Social Security program faces increasing fiscal pressure as more Americans collect benefits while fewer workers pay into the system.

Medicare expenditures are rising sharply as baby boomers age into higher healthcare utilisation years. The eldercare workforce — home health aides, nursing home staff, and assisted living workers — faces enormous demand growth at precisely the time when the working-age population is growing at its slowest pace in U.S. history. The demographic significance connects to the broader U.S. financial markets and fiscal trends.

U.S. population by sex and age group 2026 (BusinessStats Research · Census Bureau Vintage 2024): Male vs Female by age — men outnumber women under 50, women dominate 50+ · Ages 65-74: 17.7M men vs 19.7M women · Ages 75-84: 7.4M men vs 9.1M women · Ages 85+: 2.4M men vs 4.2M women (nearly 2:1) · Age 91+: 0.7M men vs 1.3M women · Male median age: 38.5 yrs · Female median age: 39.8 yrs · Sex crossover: approximately age 50. Source: U.S. Census Bureau Vintage 2024 Age-Sex Estimates · April 2026.

U.S. Population by Sex and Age — Key Statistics 2026

U.S. Age Demographics — Historical Trend 2000–2026

The transformation of America's age structure over the past 26 years is one of the most significant demographic shifts in U.S. history. In 2000, seniors aged 65+ numbered approximately 35 million (12.4% of the population), while children under 18 numbered approximately 72.3 million (25.6%). By 2024, the senior population had grown to 61.2 million (18.0%) — an increase of 26 million seniors in just 24 years — while children fell to 73.1 million (21.5%), barely growing despite the overall population expanding by nearly 60 million people.

The working-age population (18–64) grew from approximately 167 million in 2000 to 205.7 million in 2024 — a 23% increase — but its share of the population fell from 59.3% to 60.5%, masking the relative decline in the workforce compared to dependents.

The U.S. median age tells the sharpest version of this story: from 35.3 years in 2000 to a record high of 39.1 years in 2024 — an increase of nearly 4 years in a single generation. The gap between the 65+ and under-18 populations has narrowed from 37 million in 2000 (children vastly outnumbering seniors) to just 11.9 million in 2024. At current trajectories, seniors will outnumber children nationally sometime between 2030 and 2035 — a milestone already reached in 11 states and 45% of all U.S. counties.

U.S. Age Group Populations — Historical Trend 2000–2026

U.S. Population by Age — State & Regional Breakdown 2026

Age distribution varies dramatically across U.S. states and regions. Maine has the oldest population in the country with a median age of approximately 46 years, reflecting decades of outmigration by young people and in-migration of retirees. Other states with the oldest populations include Vermont (~44 years), New Hampshire (~43), West Virginia (~43), and Connecticut (~41). At the opposite extreme, Utah has the youngest median age in America at approximately 31 years — driven by its higher-than-average fertility rate (reflecting its predominantly Latter-day Saint population) and large families. Other young states include Texas (~35), Alaska (~35), California (~38), and Georgia (~37).

The Northeast region has the highest median age at 40.6 years — well above the national average of 39.1. The South (38.8) and West (38.4) are younger, driven by Sun Belt migration and higher birth rates. Among the nation's major metros, Provo-Orem, Utah has the youngest population of any large metro area, while Punta Gorda, Florida and The Villages, Florida (a massive retirement community) have the oldest. The age distribution by metro is tracked in our U.S. metropolitan areas analysis.

U.S. Median Age by Region — 2026

Aging America — The Baby Boomer Effect & What It Means

The transformation of America’s age structure is the defining demographic story of the 2020s. Baby boomers — the 76 million Americans born between 1946 and 1964 — are now aged 62 to 80, and all of them will have crossed the traditional retirement age of 65 by 2030. This has driven the 65+ population from 54.1 million in 2020 to 61.2 million in 2024 — a 13% increase in just four years, and from 16.3% to 18.0% of the total U.S. population.

The implications are vast. The old-age dependency ratio — the number of seniors (65+) per 100 working-age adults (15–64) — is rising rapidly, straining Social Security and Medicare. The potential support ratio (working-age adults per senior) has fallen to approximately 3.9 — meaning fewer than 4 workers support each retiree, compared to over 5 workers per retiree in 2000. In nearly half of U.S. counties (1,411 of 3,144), older adults already outnumber children as of 2024 — up from 31% of counties in 2020. Three major metros — Cleveland, OH; Providence-Warwick, RI-MA; and Hartford-CT — crossed into senior-majority territory for the first time in 2024. The demographic trends directly impact the financial markets tracked in our U.S. financial markets analysis.

America's aging population 2026 (BusinessStats Research · Census Bureau Vintage 2024): 65+ population: 61.2M (18.0% of U.S.) — up from 12.4% in 2004 · +13% growth 2020-2024 (fastest of any age group) · 85+: 13.4M, growing at 4.2%/yr · Seniors outnumber children in 11 states · 45% of U.S. counties have more seniors than children · Median age: 39.1 (record) · Old-age support ratio: 3.9 workers per retiree · All baby boomers will be 65+ by 2030. Source: Census Bureau Vintage 2024 · Released June 2025.

Frequently Asked Questions — U.S. Population by Sex and Age 2026