An estimated 5.4 million adults in the United States have autism, based on a CDC study that put the adult prevalence rate at 2.21%. Among children, the most recent CDC surveillance data from 2022 found that about 1 in 31 eight-year-olds met criteria for autism spectrum disorder. Combined, these figures suggest that several million Americans across all age groups are living with autism today.
Prevalence in Children
The CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network tracks autism among eight-year-olds at sites across the country. Its 2022 data, published in 2025, found a prevalence of 32.2 per 1,000 children, or roughly 1 in 31. That figure varied dramatically by location, from a low of 9.7 per 1,000 in Laredo, Texas to a high of 53.1 per 1,000 in California. These differences reflect not just biology but access to diagnostic services, school-based screening programs, and community awareness.
Earlier ADDM surveillance years show how quickly the numbers have risen. In 2000, the rate was 1 in 150. By 2010, it had climbed to 1 in 68. By 2020, it was 1 in 36. That trajectory represents a roughly fourfold increase in identified prevalence over two decades.
Prevalence in Adults
Adults are harder to count because many grew up before routine screening existed. A 2017 CDC analysis estimated that 2.21% of U.S. adults have autism, with state-level rates ranging from 1.97% in Louisiana to 2.42% in Massachusetts. Applied to state populations, the largest numbers are in the most populous states: roughly 702,000 adults in California, 450,000 in Texas, 342,000 in New York, and 329,000 in Florida.
Many of these adults were never formally diagnosed as children. Some received diagnoses later in life, while others remain undiagnosed entirely. The adult estimate is considered conservative because it relies on modeling rather than direct screening.
Why the Numbers Keep Rising
The increase in autism prevalence over the past 25 years does not necessarily mean autism itself is becoming more common. Several forces are pushing the numbers upward at the same time.
Broader diagnostic criteria play a major role. When the DSM-5 replaced the DSM-IV in 2013, it folded previously separate diagnoses like Asperger’s syndrome and PDD-NOS into a single autism spectrum disorder category. Interestingly, the newer criteria are actually stricter in some ways: studies comparing the two systems found that 9% to 54% of people who qualified under the old rules did not meet the new threshold, with a median of about 30%. But heightened public awareness and better-trained clinicians have more than compensated, catching children who would previously have been missed or labeled with something else.
Improved screening among girls and minority communities has also expanded the count. Historically, autism was identified most often in white boys, which reflected gaps in who got evaluated rather than who actually had the condition.
Differences by Race and Ethnicity
For years, white children were diagnosed with autism at higher rates than other groups. That pattern has reversed. The CDC’s 2020 surveillance data found that Asian and Pacific Islander children had the highest prevalence at 33.4 per 1,000, followed by Hispanic children at 31.6, Black children at 29.3, and white children at 24.3.
This shift likely reflects better outreach and screening in communities that were previously underserved. It does not mean autism suddenly became more common in these populations. It means clinicians and schools are now identifying children who were always there but went undiagnosed.
The Gender Gap
Boys are diagnosed with autism roughly three to four times more often than girls. This ratio has been remarkably stable over time, though researchers increasingly believe it overstates the true difference. Girls with autism tend to present differently: they may mask social difficulties more effectively, show fewer repetitive behaviors, and have special interests that look more typical to outside observers. The result is that many girls are diagnosed later or not at all, which means the real gender ratio could be closer to 2-to-1 or even narrower.
Autism and Family Income
Children with autism are disproportionately likely to live in lower-income households. According to research from the A.J. Drexel Autism Institute, 56% of children with autism lived in households below 200% of the federal poverty level, compared to 42% of children without special health care needs. About 30% lived in households below the poverty line itself.
This pattern cuts both ways. Financial hardship can limit access to early intervention and therapy, and raising a child with significant support needs can reduce a family’s earning capacity. Children with autism from low-income households tend to have more severe parent-reported symptoms and poorer overall health than their peers in higher-income families. They are also more likely to live in single-parent households and to have a sibling with a special health care need.
Children Receiving School Services
The rise in autism prevalence shows up clearly in education data. In the 2018-19 school year, 11% of all students receiving special education services under the federal IDEA program were identified with autism. A decade earlier, that figure was just under 5%. The range across states was wide, from 1% to 15%, reflecting differences in how schools identify and classify students with autism versus other developmental conditions.
These school counts capture a different slice of the population than clinical prevalence studies. A child might have a clinical autism diagnosis but receive school services under a different category, or receive autism-specific services without a formal medical diagnosis. Still, the doubling of the autism share in special education over a single decade mirrors the broader trend in clinical identification.