Early signs of autism, by age
Worried your child might be showing signs of autism? Here is the plain checklist of what to look for at each age, and exactly what to do next in Colorado.
The CDC now identifies autism in about 1 in 31 children. Signs can show by 18 months.
The earliest signs of autism are usually differences in eye contact, response to name, pointing and gestures, and play, and they often show before age 2. The CDC identifies autism spectrum disorder (ASD) in about 1 in 31 children, and says signs can appear by 18 months, with a reliable diagnosis possible by age 2. You do not need a diagnosis to act. In Colorado, a parent can start a free evaluation without one. At Budding Futures ABA, our Colorado BCBAs help families read these signs and map the next step.
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Early signs of autism, by age
These come from the CDC's age-linked list of developmental milestones. One sign alone is not a diagnosis, but a few together are worth a conversation with your pediatrician.
| Age | Possible signs to watch for |
|---|---|
| By 9 months | Little or no eye contact, no response to their name, few facial expressions |
| By 12 months | No back-and-forth babble, no waving or other gestures, no simple games like pat-a-cake |
| By 15-18 months | No first words by 15 months, does not point to show you something interesting by 18 months |
| By 24 months | No two-word phrases, does not notice when others are upset, little pretend play |
| Any age | Lines up toys and is upset by change, repeats words (echolalia), focuses on parts of objects, spins or flaps, strong reactions to sound, light, or texture |
What are the most common early signs of autism?
The signs parents notice first are usually limited eye contact, not responding to their name, not pointing or waving, lining up or spinning toys, repeating words, and sometimes losing words they used to say. These are differences in how a child connects and plays, not in how smart they are.
“Pointing was absolutely the biggest one. If your child isn't pointing with eye contact at 18 months, something is probably up.”
When autism parents look back at the first signs they noticed, the same few come up again and again: not pointing, no response to their name, hand flapping, and lost words. Real parent language, not a clinical list.
Parent in r/Autism_Parenting, “earliest symptoms” thread · read the thread →
At what age do signs of autism usually appear?
Often before age 2. Most parents report their first concern by their child's second birthday, years before an autism diagnosis is made. The CDC says autism can be detected by 18 months and reliably diagnosed by age 2, so starting early matters.
Is it a speech delay or autism?
It can be either, and both are worth acting on. A late talker who still points, shares, and plays pretend is different from a child who is quiet and also avoids connecting. You do not have to tell them apart yourself. The same free evaluation covers a speech delay or autism.
What if my child loses skills they used to have?
Tell your doctor soon. About 30% of autistic children lose skills like words or eye contact, usually around 20 months. Losing a skill is not something to watch and wait on. It is a reason to ask for an evaluation now.
Do these signs mean my child is autistic?
Not by themselves. A checklist is a screening tool, not a diagnosis. Many children with one or two of these signs are not autistic. But if you see several, trust your gut and get your child screened. Your pediatrician does an autism screening at the 18- and 24-month visits, and you can ask any time.
What do I do next in Colorado?
You can start a free evaluation yourself, today, without a diagnosis. The table below shows where to begin by your child's age. After a diagnosis, Budding Futures provides in-home ABA across Colorado and helps you take the next step after a diagnosis.
What to do next in Colorado
You do not need to wait for a diagnosis to begin. Colorado has free programs you can start on your own.
| Your child's age | Where to start in Colorado (free) | What happens |
|---|---|---|
| Birth to age 3 | Early Intervention Colorado (call 1-888-777-4041, or refer yourself) | A free evaluation and services, with no cost and no diagnosis needed first. |
| Age 3 and older | Child Find through your local school district | A free evaluation, finished within 60 days of your written okay. |
| Any age | Your pediatrician | An autism screen (M-CHAT-R) at the 18- and 24-month visits, then a referral for a full evaluation. |
| After a diagnosis | In-home ABA with a Colorado BCBA | Budding Futures builds the plan, checks your Medicaid or insurance, and starts with no current waitlist. |
After an autism diagnosis, Budding Futures provides in-home ABA across Colorado, works with Health First Colorado (Medicaid) and major insurers, and starts families with no current waitlist. A Board Certified Behavior Analyst, Rachel Blackburn, reviews each plan.
Sources
Plain-language summaries of autism signs come from these authorities. We link the originals so you can read them yourself.
CDC, Signs and Symptoms of Autism Spectrum Disorder
The federal list of autism signs, tied to specific ages from 9 months on.
CDC, Autism Prevalence (ADDM Network, 2022)
The 2025 report finding autism in about 1 in 31 eight-year-old children.
Becerra-Culqui et al. (2018), J Autism Dev Disord
Most parents report their first concern by age 2, years before diagnosis.
Early Intervention Colorado
Free evaluation and services for Colorado children birth to age 3.
American Academy of Pediatrics (HealthyChildren.org)
Why pediatricians screen for autism at the 18- and 24-month visits.
Not sure what you are seeing? Talk to a Colorado BCBA
We can talk through the signs, point you to the right free evaluation, and if your child has a diagnosis, build an in-home plan and check your Medicaid or insurance.