Approximately 2.2% of adults over 18 are estimated to have autism spectrum disorder (ASD). Recent studies indicate that diagnoses among adults are increasing, with the sharpest rise seen in individuals aged 26 to 34.  

Although receiving an autism diagnosis later in life can be difficult, it can also open new avenues for support and self-understanding. 

Common Symptoms of Autism 

Autism presents differently in each person, but generally, it involves challenges in two key areas: 

1. Social Communication and Interaction 

Adults with ASD may struggle to: 

• Hold conversations 
• Express emotions 
• Understand others' thoughts or feelings 
• Make eye contact 
• Read body language 
• Control vocal tone (e.g., speaking loudly or monotonously) 
• Form friendships 
• Navigate social settings 

2. Restricted and Repetitive Behaviors 

These may include: 

• Repetitive movements, speech, or actions (like rocking or hand-flapping), sometimes as a form of self-soothing 
• A strong preference for routines, with even small changes causing distress 
• Deep, focused interests in specific subjects, numbers, or facts 
• Sensory sensitivities, such as being overly reactive to light, noise, or temperature — or being unusually unresponsive 

Despite these challenges, many adults with ASD possess exceptional memory, attention to detail, and excel in fields such as math, science, music, or art. 

How Autism May Appear Differently in Adults 

While adult symptoms mirror those seen in children, many adults with ASD have learned to “mask” or hide their traits. This can lead to exhaustion, stress, anxiety, and depression. 

Adults with ASD often describe feeling out of place in social situations, preferring solitude, and struggling with interpersonal relationships and perspective-taking. They typically value structure and predictability, and may experience distress or anger when routines are disrupted. Their interests are often intense and specific. 

Symptoms may fluctuate, especially during major life changes such as starting college, beginning a new job, or entering or ending a relationship. Adults with ASD also face increased risk of mental health conditions — one study found those diagnosed in adulthood were nearly three times more likely to have mood, anxiety, or personality disorders than those diagnosed as children. 

Diagnosing Autism in Adults 

Many adults with ASD were never formally identified during childhood and remain undiagnosed. If you believe you or someone you know may have ASD, consult a neuropsychologist, psychologist, or psychiatrist with experience in ASD. 

There is no single test for autism. Diagnosis involves: 

• Reviewing childhood history (sometimes including interviews with family members) 
• Discussing current functioning, including social life, work, and relationships 
• Cognitive assessments to evaluate attention, memory, and problem-solving 
• ASD-specific assessments, such as the Autism Diagnostic Observation Schedule (ADOS-2) and the Childhood Autism Rating Scale (CARS), both validated for adult use 

Barriers to an Adult Diagnosis 

Obtaining an ASD diagnosis in adulthood comes with challenges: 

• Limited providers: Few specialists focus on diagnosing and treating adults with ASD. Primary care doctors may offer referrals, and organizations like Autism Speaks can help locate providers. 
• Cost: Evaluations can range from $2,000 to $6,000, and insurance coverage varies. Some clinics offer sliding scale fees. 
• Wait times: Appointments may take months to over a year. 
• Identity adjustment: A diagnosis can prompt shifts in self-perception, requiring time and mental health support to process. 

Benefits of an Adult Autism Diagnosis 

Despite the challenges, an ASD diagnosis in adulthood can be life-changing: 

Access to Treatment 

With a diagnosis, individuals can seek therapy to improve communication, emotional regulation, and relationships. Since people with ASD are four times more likely to experience depression, therapy — particularly cognitive behavioral therapy (CBT) — can help manage co-occurring issues like anxiety and insomnia. 

Medications may also be used to address specific symptoms: 

• SSRIs to reduce repetitive behavior and improve mood 
• Antipsychotics to decrease aggression and repetitive actions 
• Stimulants to enhance focus and reduce hyperactivity 

Other Key Benefits 

• Self-understanding and acceptance: A diagnosis can clarify long-standing difficulties and highlight personal strengths. 
• Access to services: Occupational therapy and social skills training may become available through insurance or service providers. 
• Workplace protection: The Americans with Disabilities Act (ADA) ensures reasonable accommodations, such as noise-canceling headphones or flexible lighting. 
• Community support: Many support groups and social communities exist for autistic adults. 

Post-Diagnosis Resources and Support 

After a diagnosis, a variety of supports are available: 

• Employment support: Adults with ASD may qualify for vocational rehabilitation (VR) to address job challenges or, if unable to work, Supplemental Security Income (SSI). 
• Support groups: Online and in-person groups provide community and connection. 
• Coaching services: Organizations like the Association for Autism and Neurodiversity offer coaching for skills such as executive functioning and communication.