What Age Is Autism Usually Diagnosed? Early Signs & Timelines

Spotting autism early can make a big difference. So, what age is autism usually diagnosed? Most children show signs by 12–24 months, but the average age of diagnosis is often later.

What Age Is Autism Usually Diagnosed? Quick Answers

• Early Signs Appear: Signs of autism can show up as early as 12 months. Some children display differences in eye contact, language, or play by 18 months.
  
• Screening Recommendations: The American Academy of Pediatrics recommends autism screening at 18 and 24 months.
  
• Average Age of Diagnosis: Research shows the mean age at diagnosis is between 3.5 and 5.8 years (about 43–69 months), but many children are not diagnosed until after age 4.
  
• Why the Delay? Some children meet milestones and then regress around 18–24 months. Others may be diagnosed later due to milder symptoms or access to specialists.

At Epic Minds Therapy, we often meet families whose children were first flagged at a routine checkup. Studies confirm early diagnosis—before age 3—leads to better outcomes and more effective support.

Ready for Answers?

Knowing what age is autism usually diagnosed? is the first step. Want guidance on early signs or next steps? Call Epic Minds Therapy and let’s start your journey with answers and support.

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