Signs of autism at 18 months.
Clinically reviewed by Ruth Gluck, MSEd, BCBA
At 18 months, the early signs of autism are mostly about connection: a toddler who doesn't point at things to show you, doesn't turn when you call their name, uses few or no words, and rarely brings you into their play. One sign alone proves nothing — but together, they're a reason to ask, not to wait.
Why 18 months matters
Eighteen months is the age when the early social skills — pointing, showing, sharing a look with you — are expected to be up and running. It's also when your child's doctor is supposed to screen for autism: checkup guidelines call for a short screening questionnaire, usually the M-CHAT, at the 18- and 24-month visits.
That makes this checkup the easiest moment to raise what you've noticed. You don't need to arrive certain. 'I've been wondering about a few things' is exactly how these conversations are supposed to start.
What are the signs of autism at 18 months?
No single item on this list is a diagnosis. What matters is the pattern — several of these, showing up most days:
- Not pointing at things to show you — no 'look at that!' finger, no holding toys up for you to see
- Not turning when you call their name, even though their hearing is fine
- Few or no words, and not making up for it with gestures like waving or reaching
- Little back-and-forth — you smile, they don't smile back; you point, they don't look where you're pointing
- Playing alone in a way that shuts others out, or playing with toys in one repeated way — lining up, spinning, dropping
- Strong reactions to sounds, textures, or changes that other toddlers shrug off
- Losing words or skills they used to have — this one deserves a call to the doctor this week, not someday
What's usually not a red flag
Plenty of things worry parents at 18 months and turn out to be nothing. A toddler who is slow to talk but points, gestures, and drags you to what they want is communicating fine — just not with words yet. Tantrums are standard toddler equipment. Loving a favorite show, insisting on a favorite cup, or being shy with strangers are all ordinary.
The difference is connection. A late talker who is tuned in to you — checking your face, showing you things, following your point — has a bridge that words can cross later. When that bridge itself looks thin, that's the thing worth asking about.
What should you do if you're seeing these signs?
Two moves, both free. First, tell your child's doctor exactly what you've noticed and ask two direct questions: 'Can you screen my child for autism?' and 'Can you refer us for a full evaluation?' Second, call your state's early intervention program — every child under three is entitled to a free developmental evaluation, no doctor's referral needed.
And if you want a person to help you sort out where to call first, that's what we do all day. Our get-a-diagnosis guide maps the evaluation path for families in Kansas and Colorado, and the phone call costs nothing.
The wait-and-see trap
You may hear 'boys talk late,' 'his cousin was the same way,' or 'let's look again at two.' Sometimes those reassurances turn out right. But waiting has a real cost and checking has none: evaluation waitlists run long, and a toddler's brain learns faster now than it ever will again.
So do both. Keep loving the wait-and-see optimism of the people around you — and get your child's name on an evaluation list anyway. If the worry turns out to be nothing, you've lost nothing. If it's something, you've saved months.