Research compiled by New Frontiers | Last updated: July 2026
Approximately 15.5 million adults in the United States, or 6% of the national population, have been diagnosed with ADHD, along with 7 million children (11.7%). ADHD, also known as Attention-Deficit/Hyperactivity Disorder, is a condition affecting the brain, which causes individuals to experience inattention, hyperactivity, and impulsivity. People with ADHD may find themselves struggling to maintain focus on tasks or conversations, feeling the constant need to move or fidget, and acting impulsively or overly quickly in certain situations. There are various types of ADHD, and all individuals are affected in different ways or to different degrees.
This guide examines the average age at which people are diagnosed with ADHD, either in childhood or adulthood, and also lays out key figures regarding the prevalence of ADHD among various demographics, age levels, and treatment plans. Additionally, this guide includes data on ADHD responses, funding, and trends across the regions and states of America, examining how school systems and other public services have advocated for those with ADHD. All data was compiled from publicly available sources in July 2026, including organizations such as the Centers for Disease Control (CDC) and the National Institute of Mental Health (NIMH).
ADHD in Childhood
ADHD is often diagnosed in childhood. Frequently, parents will begin the process of having their child examined and tested for ADHD if they notice common symptoms such as inattention, hyperactivity, and impulsivity. The average age of diagnosis for childhood ADHD varies slightly by the severity of ADHD a child is diagnosed with. The overall median age of diagnosis is 6 years, while those with more severe ADHD may be diagnosed younger and those with milder ADHD may be diagnosed older.
Statistically, ADHD affects racial and ethnic demographics in the U.S. at different percentages, with White and Black populations having the greatest prevalence of ADHD. ADHD prevalence also varies among children by age group.
Median Age of Onset and Diagnosis
| Metric | Age |
|---|---|
| Median age of ADHD onset | 6 years |
| Median age of diagnosis for Severe ADHD | 4–5 years |
| Median age of diagnosis for Moderate ADHD | 6–7 years |
| Median age of diagnosis for Mild ADHD | 7–8 years |
Sources: Table 1
Childhood ADHD Prevalence by Demographic
| Demographic | Rate of Childhood ADHD Diagnosis |
|---|---|
| White | 11% |
| Black | 11% |
| American Indian/Alaska Native | 8% |
| Asian | 3% |
| Hispanic | <3% |
Sources: Table 2
ADHD Prevalence Among U.S. Students by Age/Level
| Student Level | Prevalence of ADHD |
|---|---|
| Elementary School (ages 5–11) | 6.9%–10.8% |
| Middle/High School (ages 12–17) | 12.1%–17.1% |
| All K–12 (ages 5–17), National Average | 11.3% |
| All Children (ages 3–17) | 11.7% (~7 million children) |
| College Students, Self-Reported Diagnosis | 5.6% |
| College Students, Self-Report Survey | ~15% |
Sources: Table 3
ADHD in Adulthood
When diagnosed in adulthood, ADHD showcases a slight difference in terms of the average age of diagnosis among males and females. Compared to children, the prevalence of ADHD among adult populations is slightly less, likely due to improved diagnostic tools and criteria for evaluating ADHD among children. While ADHD diagnosis and awareness has increased, the percentage of those seeking treatment for ADHD varies by age group, though numbers are increasing as time passes.
Average Age of Adult ADHD Diagnosis
| Population | Average Age of ADHD Diagnosis |
|---|---|
| Adult Males | 24.13 years |
| Adult Females | 28.96 years |
Sources: Table 4
Prevalence of ADHD in the U.S. by Age Group
| Age Group | ADHD Prevalence |
|---|---|
| Children, ages 3–17 | 11.7% |
| Children, ages 5–11 | 6.9%–10.8% |
| Adolescents, ages 12–17 | 12.1%–17.1% |
| Adults, ages 18–44 | 4.4% (current); 8.1% (lifetime) |
| Adults, ages 30–44 | 4.4%–6.0% |
| Older adults, 50+ | 2.18% |
| Adults, all ages 18+ | ~6.0% (15.5 million adults) |
Sources: Table 5
Number of ADHD-Diagnosed People in the U.S. Receiving Treatment by Age Group
| Age Group | Percentage Receiving Treatment |
|---|---|
| Children, ages 2–5 | 18%–47% |
| Children, ages 6–11 | 69% |
| Children, ages 3–17 (overall) | ~62%–77% |
| Adults, 18+ (overall) | 63.5% |
Sources: Table 6
State-by-State ADHD Statistics
The prevalence of childhood ADHD in America varies by state, likely due to differences in diagnostic and reporting procedures across different states. Currently, Louisiana has the highest prevalence of ADHD diagnoses, at 16.3%, while California has the lowest prevalence, at 5.6%–6.1%. Overall statistics show that ADHD is more prevalent in the Southern and Midwestern U.S. than other regions. However, the top 5 state school systems in terms of ADHD awareness include three states from the Northeast.
On average, the United States spends approximately $13,127 per affected student to treat and manage ADHD.
Prevalence of Childhood ADHD Across Major Reporting U.S. States
| State | Childhood ADHD Prevalence |
|---|---|
| Louisiana | 16.3% |
| Rhode Island | 15.9% |
| South Carolina | 15.8% |
| Maine | 15.5% |
| West Virginia | 15.1% |
| California | 5.6%–6.1% |
Sources: Table 7
Regional ADHD Trends in the U.S.
| Region | ADHD Prevalence (General Population) |
|---|---|
| South | 11.3% |
| Midwest | 10.0% |
| Northeast | 9.1% |
| West | 6.9% |
Sources: Table 8
Top 5 State School Systems for ADHD/Special Education Awareness
| Ranking | State | Score (/100) | ADHD Statistics |
|---|---|---|---|
| 1 | Vermont | 69.69 | 50.5% of children with ADHD receive a school-based early intervention/special-ed plan |
| 2 | North Carolina | 62.87 | 52.6% of students with learning/developmental challenges get early educational support |
| 3 | Maine | 62.80 | 50.5% receive intervention plans; 37.1% get needed therapy access |
| 4 | Massachusetts | 62.16 | 36.8% of students with ADHD/anxiety/ASD/other conditions receive adequate therapy |
| 5 | Texas | 58.87 | 49.2% receive tailored education plans; strongest academic outcomes |
Sources: Table 9
Public Funding for Special Education in the U.S., Key Figures
| Metric | Figure |
|---|---|
| Number of States With Published Funding Samples | 24 states (5,694 districts) |
| Number of Students With Disabilities | ~3 million (41% of national total) |
| Highest-Spending State for Special Education | Connecticut ($24,443 per pupil) |
| Lowest-Spending State for Special Education | Mississippi ($5,265 per pupil) |
| National Average Spending | $13,127 per student |
Sources: Table 1010
References
Table 1:
- Attention-Deficit/Hyperactivity Disorder (ADHD). (n.d.). National Institute of Mental Health (NIMH). https://www.nimh.nih.gov/health/statistics/attention-deficit-hyperactivity-disorder-adhd
- Trends in Health Care Provider-Diagnosis and Treatment for ADHD. (2019, August 29). Centers for Disease Control and Prevention. https://archive.cdc.gov/www_cdc_gov/ncbddd/adhd/features/key-findings-adhd72013.html
- Yes, ADHD diagnoses are rising, but that doesn’t mean it’s overdiagnosed. (n.d.). https://www.adhdevidence.org/blog/yes-adhd-diagnoses-are-rising-but-that-doesnt-mean-its-overdiagnosed
Table 2:
- Data on ADHD in Children. (2026, July 8). Centers for Disease Control. https://www.cdc.gov/adhd/data/index.html
Table 3:
- QuickStats: Percentage* of children and adolescents aged 5–17 years who had ever received a diagnosis of Attention-Deficit/Hyperactivity Disorder,† by urbanization level§ and age group — National Health Interview Survey, United States, 2020–2022¶. (2024). MMWR Morbidity and Mortality Weekly Report, 73(5), 116. https://doi.org/10.15585/mmwr.mm7305a6
- Data on ADHD in Children. (2026, July 8). Centers for Disease Control. https://www.cdc.gov/adhd/data/index.html
- Hotez, E., Rosenau, K. A., Fernandes, P., Eagan, K., Shea, L., & Kuo, A. A. (2022). A National Cross-Sectional Study of the Characteristics, Strengths, and challenges of college students with Attention Deficit Hyperactivity Disorder. Cureus, 14(1), e21520. https://doi.org/10.7759/cureus.21520
- Neilsen, J. (2026, July 8). 24 ADHD Statistics for 2024. ADHD Advisor. https://www.adhdadvisor.org/learn/adhd-statistics-and-facts
Table 4:
- Kuntz, L. (2025, October 13). Women Are Diagnosed With ADHD 5 Years Later Than Men. Psychiatric Times. https://www.psychiatrictimes.com/view/women-are-diagnosed-with-adhd-5-years-later-than-men
Table 5:
- Data on ADHD in Children. (2026, July 8). Centers for Disease Control. https://www.cdc.gov/adhd/data/index.html
- QuickStats: Percentage* of children and adolescents aged 5–17 years who had ever received a diagnosis of Attention-Deficit/Hyperactivity Disorder,† by urbanization level§ and age group — National Health Interview Survey, United States, 2020–2022¶. (2024). MMWR Morbidity and Mortality Weekly Report, 73(5), 116. https://doi.org/10.15585/mmwr.mm7305a6
- Attention-Deficit/Hyperactivity Disorder (ADHD). (n.d.). National Institute of Mental Health (NIMH). https://www.nimh.nih.gov/health/statistics/attention-deficit-hyperactivity-disorder-adhd
- Attention-Deficit/Hyperactivity Disorder Diagnosis, Treatment, and Telehealth Use in Adults — National Center for Health Statistics Rapid Surveys System, United States, October–November 2023. (2024, October 10). Centers for Disease Control. https://www.cdc.gov/mmwr/volumes/73/wr/mm7340a1.htm
- Caron, C. (2024, December 11). ADHD Diagnosis in Older People Has Increased. The New York Times. https://www.nytimes.com/2024/12/11/well/mind/adhd-diagnosis-older-middle-age.html
- MacMillan, C. (2025, August 12). ADHD in adults: a psychiatrist explains. Yale Medicine. https://www.yalemedicine.org/news/adhd-in-adults
- General Prevalence of ADHD in Adults – CHADD. (2026, January 16). CHADD. https://chadd.org/about-adhd/general-prevalence-adults/
Table 6:
- Neilsen, J. (2026, July 8). 24 ADHD Statistics for 2024. ADHD Advisor. https://www.adhdadvisor.org/learn/adhd-statistics-and-facts
- Diena, Y. (2023, May 24). 59 ADHD Statistics, Facts & Demographics. https://www.ambitionsaba.com/resources/adhd-statistics
- Attention-Deficit/Hyperactivity Disorder Diagnosis, Treatment, and Telehealth Use in Adults — National Center for Health Statistics Rapid Surveys System, United States, October–November 2023. (2024, October 10). Centers for Disease Control. https://www.cdc.gov/mmwr/volumes/73/wr/mm7340a1.htm
Table 7:
- Neilsen, J. (2026, July 8). 24 ADHD Statistics for 2024. ADHD Advisor. https://www.adhdadvisor.org/learn/adhd-statistics-and-facts
- Bozinovic, K., McLamb, F., O’Connell, K., Olander, N., Feng, Z., Haagensen, S., & Bozinovic, G. (2021). U.S. national, regional, and state-specific socioeconomic factors correlate with child and adolescent ADHD diagnoses pre-COVID-19 pandemic. Scientific Reports, 11(1), 22008. https://doi.org/10.1038/s41598-021-01233-2
- Habas, C. (2026, May 28). ADHD statistics: Prevalence in children and adults. The Checkup. https://www.singlecare.com/blog/news/adhd-statistics/
Table 8:
- Updated analysis of ADHD prevalence in the United States: 2018-2021. (n.d.). https://www.adhdevidence.org/blog/updated-analysis-of-adhd-prevalence-in-the-united-states-2018-2021
Table 9:
- The State of Special Education: The Best U.S. States for Supporting Students. (2025, November 6). https://blazerworks.com/resources/best-states-for-special-education/
Table 10:
- Campbell, Z. (2026, January 5). Who pays for special education? An analysis of federal, state, and local spending by states and districts. Bellwether. https://bellwether.org/publications/who-pays-for-special-education/
