Early signs of autism in toddlers mostly show up in how a child communicates and connects, such as pointing, sharing and answering to their name. Looking for autism signs? 18 months is the age when the American Academy of Pediatrics (AAP) recommends the first autism-specific screening for every child, with a second at 24 months. This checklist covers what to watch at 12, 18 and 24 months, and what to do next in California.
Quick answer
Autism signs at 18 months: Watch whether your toddler points to show you something interesting, brings things to share, answers to their name, uses gestures and tries a few words. Missing several of these, or losing words or skills, is a reason to ask your pediatrician for a screening. In California, you can also call Early Start without a diagnosis.
Last checked: November 10, 2026. This is general information, not legal or medical advice.
What are the early signs of autism in toddlers?
The earliest signs are usually differences in social communication. A toddler may not point to share interest, may not respond to their name, may use few gestures or may seem to play alone most of the time. Some children also show repeated movements, strong routines or unusual reactions to sounds, textures or lights.
This checklist is not a diagnostic tool. One missed item does not mean a child is autistic. A pattern of several signs, or any loss of skills, is a reason to talk with your child’s doctor. Only a trained professional can diagnose autism.
The items below come from the CDC’s “Learn the Signs. Act Early.” milestones and AAP guidance.
Checklist: signs to watch at about 12 months
The CDC lists these signs to watch by 12 months:
- Does not play simple back-and-forth games like pat-a-cake.
- Uses few or no gestures, such as waving bye-bye.
- Rarely responds to their name (the CDC lists this from 9 months).
- Shows few facial expressions, such as happy, sad or surprised (also from 9 months).
The AAP notes that a 12-month-old on the spectrum may seem to ignore a parent. Many parents first wonder about hearing, so ask about a hearing check too.
Autism signs at 18 months: the checklist
At 18 months, the key skill is joint attention: sharing interest in something with another person. Most children point to show you something, like a dog, and look back at your face. The AAP says an autistic toddler may point mainly to get something they want, or lead a parent by the hand to it.
Signs to watch by 18 months:
- Does not point to show you something interesting.
- Does not bring or hold up objects just to share them (the CDC lists this from 15 months).
- Does not try to say three or more words besides “mama” or “dada.”
- Does not follow a simple one-step direction without gestures, such as “give me the cup.”
- Does not look at a few pages in a book with you.
- Avoids or does not keep eye contact.
The 18-month well-child visit is when your pediatrician should screen for autism. The CDC’s 18-month developmental milestones checklist from the CDC lists every skill, including movement skills, so you can bring it to the visit.
Signs to watch at 24 months
The second AAP autism screening happens at the 24-month visit. Signs to watch by 24 months:
- Does not notice when others are hurt or upset.
- Does not look at your face to see how to react in a new situation.
- Does not say two words together, such as “more milk.”
- Does not point to things in a book when asked, or to two body parts.
- Uses no gestures beyond waving and pointing, such as nodding yes or blowing a kiss.
Repeated behaviors and sensory differences
The CDC also lists behaviors that can appear at any age. These include lining up toys and getting upset when the order changes, and playing with toys the same way every time. Others are focusing on parts of objects such as wheels, flapping hands, rocking or spinning, and strong reactions to sounds, smells, tastes or textures.
Loss of skills
According to the AAP, about 25 percent of children later diagnosed with autism develop some words and then stop using them, typically between 15 and 24 months. Losing words or social skills at any age is always worth raising with your doctor right away.
| Age | Signs to watch | What to do |
|---|---|---|
| About 12 months | No pat-a-cake or waving, rarely answers to name, few facial expressions | Mention it at the 12-month visit; ask about a hearing check |
| About 18 months | No pointing to show, no sharing objects, fewer than 3 words | Autism screening at the 18-month visit; call Early Start if concerned |
| About 24 months | No 2-word phrases, doesn’t notice others’ feelings, few gestures | Second autism screening; ask for an evaluation referral |
| Any age | Loss of words or skills; strong repeated behaviors | Call the pediatrician now; don’t wait for the next visit |
What is M-CHAT screening?
The M-CHAT-R/F (Modified Checklist for Autism in Toddlers, Revised, with Follow-Up) is a common autism screening questionnaire for toddlers about 16 to 30 months old. A parent answers 20 yes-or-no questions, and the pediatrician or clinic staff score it. Scoring takes under two minutes.
- Low likelihood (0 to 2): no further action, though children screened before age 2 are screened again after their second birthday.
- Medium (3 to 7): the clinician asks follow-up questions about the “at-risk” answers. If concerns remain, the child is referred for an evaluation.
- High (8 to 20): referral for a diagnostic evaluation and for early intervention eligibility.
The tool is designed to catch as many children as possible, so many children who screen positive are not autistic. Its authors note those children often have other delays that still need an evaluation. Screening tools do not diagnose autism.
The AAP’s parent site explains these signs further in early signs of autism spectrum disorder on HealthyChildren.org.
What to do next in California
If several items fit your child, act now rather than waiting. In California, you can take these steps at the same time:
- Talk with your pediatrician. Ask for the M-CHAT-R/F or another screening, a hearing test, and a referral to a specialist if concerns remain.
- Call Early Start. Children under 3 can get an evaluation through the regional center or school district without a diagnosis or a doctor’s referral. Call (800) 515-BABY. The agency has 45 days from referral to assess your child and hold a planning meeting. Read how the Early Start program in California works.
- Ask about a diagnosis. An Early Start evaluation is not always an autism diagnosis. Our guide on how to get an autism diagnosis in California compares the routes.
- Plan for age 3. After the third birthday, regional center services continue only for children who meet Lanterman Act or provisional eligibility. Learn how to apply for regional center services.
Frequently asked questions
My child doesn’t point at 18 months. Does that mean autism?
Not on its own. Pointing to show something is one important skill, but a single missing skill is not a diagnosis. Mention it at the 18-month visit and ask for a screening. If your child also has few words or rarely answers to their name, ask for an evaluation.
Can I fill in the M-CHAT myself?
Yes. It is a parent questionnaire, and the authors offer it free at mchatscreen.com. Bring your answers to your pediatrician, who can score them, ask the follow-up questions and decide on a referral. A score on its own does not tell you whether your child is autistic.
Can autism be diagnosed at 18 months?
Some children are evaluated soon after an 18-month screening, but the timing depends on the child and the specialist. You don’t need to wait for a diagnosis to get help. Early Start serves children under 3 with a developmental delay, with or without an autism label.
Next step
If the checklist raised concerns, the next step is an evaluation. Our guide to autism services in California shows how screening, Early Start, diagnosis and regional centers fit together.
Want to talk with someone first? Call the Autism Society of California information line at 1-800-869-7069, see our list of free autism helplines in California, or reach families through your local Autism Society affiliate.