Signs of autism in toddlers: what to look for and how to seek support

Q: Does hand flapping mean my toddler has autism?

Not necessarily. Repetitive movements like hand flapping, rocking, or spinning are common in autistic children and serve as a form of self-regulation, but they also appear in many children who are not autistic. Taken alone, they are not a reliable indicator of anything. What matters most is the whole picture: how your child communicates, responds to others, and navigates their world. If you are noticing several differences together, that is worth discussing with your GP rather than any single sign in isolation.

12 to 36 months · Development · Updated July 2026 · All articles

If you are reading this at 2am because something your toddler does has been sitting quietly in the back of your mind, you are in good company. Wondering whether your child might be autistic is one of the most searched things parents look up, and one of the most emotionally loaded. Whatever brought you here, this article is for you.

There is nothing alarming in what follows. Autism is not something that went wrong. It is a different way of processing the world, of communicating, and of experiencing sensation and social connection. Understanding it earlier, rather than later, means your child can get the right kind of support during the years when it makes the most difference. That is what this article is about.

What autism is

Autism is a neurodevelopmental difference. It affects how people communicate, process information, and experience the world around them. It is not a disease, not a failure of parenting, and not something that happened to your child. It is a different kind of brain, present from birth, that shapes how a person thinks, feels, and relates to others.

Autism is described as a spectrum because it looks different in every person who has it. Some autistic people use spoken language fluently and live very independently. Others communicate in different ways and need more support with daily life. Most autistic people sit somewhere across this wide range, and many have a mix of strengths and areas where they need help. No two autistic people are the same.

Autistic people are not defined by their challenges. Many describe their autism as a core part of who they are, shaping how they connect deeply with things they love, how they notice details others miss, and how they experience the world with unusual intensity. A diagnosis is not a verdict. It is a map that helps you understand your child and find the right support.

Why early recognition matters

The toddler years are a period of extraordinary brain development. The connections forming between 12 and 36 months are laying foundations for language, social understanding, and learning. During this window of high brain plasticity, support lands differently than it does later. Not because anything needs to be fixed, but because this is when the right kind of help makes the most practical difference.

Speech and language therapy, occupational therapy, and ASD-specific early intervention programmes can all help an autistic toddler develop communication strategies, manage sensory experiences, and build the skills that will help them in daily life. Early support is not about changing who your child is. It is about helping them understand and be understood, on their own terms.

The goal of noticing possible signs early is not for you to diagnose your child. It is so that if there is something worth exploring, you can start that conversation with a professional sooner rather than later. Waiting lists for formal assessment can be long, and accessing support before a diagnosis is often possible.

Signs that may be worth a professional conversation

The list below describes things that some autistic children do in their first three years. They are not a diagnostic checklist, and they are not proof of anything. Many of these signs appear in children who are not autistic, and some autistic children show very few of them. What the list gives you is a basis for a conversation with your GP or health visitor.

If you notice several of these things together, or if something has shifted or been lost, that is the moment to pick up the phone.

Communication and social connection

Not pointing to share interest by around 14 months. Proto-declarative pointing is pointing to share something with you rather than to request it. "Look at that!" rather than "I want that." It is a key early marker of shared attention, and its absence is one of the most robust early signs worth discussing.
Not waving bye-bye or copying gestures by 12 months. Imitation is central to early learning. A toddler who does not mirror simple gestures may be finding social imitation harder than expected.
No babbling by 12 months. Babbling is the precursor to speech and reflects a child tuning in to the sound patterns around them.
No single words by 16 months. A toddler who has not produced any recognisable words by this age is worth checking in with a professional, regardless of other development.
No two-word phrases by 24 months. "More milk", "daddy go", "big dog" are the kind of combinations expected by two years old. If your child has words but is not yet joining them, mention it.
Loss of language or skills they had previously acquired. This is always a prompt to seek a review promptly, at any age. A child who had words and lost them, or who was making eye contact and no longer does, needs to be seen. Loss of skills is a specific flag under NICE NG142 that warrants urgent referral.
Limited or inconsistent eye contact. Many autistic children do make eye contact, especially with people they know well. But if your child rarely seeks your gaze in shared moments of excitement, connection, or communication, that is worth noting.
Limited response to their own name. A child who does not reliably turn when called by name may have a hearing difference, may be autistic, or may have another reason worth exploring. It is one of the signs NICE NG142 specifically highlights as warranting referral.
Limited interest in other children or in imitative play. Young toddlers are not expected to play cooperatively, but most show some curiosity about other children and engage in simple imitative play. A child who consistently seems uninterested in peers or in copying simple games may be finding social interaction harder than expected.

Sensory experiences and routines

Unusual sensory responses. This can go in either direction. Some autistic children are very distressed by certain sounds, textures, lights, or smells that do not bother other children. Others seek very intense sensory input, pressing their face into surfaces, staring at lights, or craving deep pressure. Both patterns can be signs of sensory processing differences.
A strong preference for sameness and significant distress at change. Many toddlers like routine, but an autistic child may show unusually intense distress at small changes to their environment or schedule, such as a different route home, a different cup, or a change in where something is placed.
Repetitive movements. Hand flapping, body rocking, spinning, or finger movements are common in autistic children and are a form of self-regulation. They are not harmful and should not be suppressed. They may also appear in children who are not autistic. In context with other signs, they are worth mentioning.

These signs do not equal a diagnosis

This is important enough to say plainly. Many of the signs above appear in children who are not autistic. A speech delay can have many causes, including hearing loss, a temporary lag, a language-rich but slow-to-speak temperament, or bilingualism. Sensory sensitivity and love of routine are common in children with anxiety, sensory processing differences that are not autism, and many children who are simply themselves.

Only a specialist assessment can tell you whether your child is autistic. That assessment takes time, involves multiple professionals, and looks at the whole child across different settings. What you can do is observe, record specific things you have noticed, and share them with your GP or health visitor. You are not trying to reach a conclusion. You are opening a conversation.

A note about autism in girls

Autism is diagnosed more often in boys than in girls, but research increasingly shows that this gap may reflect a real difference in how autism presents rather than in how common it is. Many autistic girls are missed or diagnosed much later because they are better at social mimicry and masking.

Masking means copying the social behaviour of peers well enough to appear neurotypical in structured settings, while finding it exhausting and difficult. An autistic girl may make eye contact, seem socially engaged, and be described as "just a bit anxious" or "a people pleaser" for years before her autism is recognised. She may have intense, focused interests that are more socially accepted and therefore less visible to others.

If you have a daughter and you have a quiet feeling that something is different, trust it. Raise it. Girls are underserved by an assessment system built around a male presentation of autism, and early recognition matters just as much for them.

How to seek support

The first step is a conversation with your GP or health visitor. When you go, bring your observations. The more specific you can be, the more useful it will be. Not "I am worried about his development" but "He has never pointed at things to show me, he does not turn when we call his name, and he lost the three words he had at 14 months." Concrete, observed, specific.

Under NICE NG142 (the NHS clinical guideline on autism recognition and referral), GPs and health visitors should refer a child for a specialist developmental assessment if there is any reasonable cause to suspect autism. You do not need to prove anything or overcome a threshold. You need your concerns to be heard and acted on.

A specialist assessment in the UK is usually carried out by a multidisciplinary team including a developmental paediatrician, a speech and language therapist, and a clinical psychologist. It takes into account behaviour at home and in other settings, parental observations, and direct assessment of the child. Waiting times vary significantly by area and can be many months or longer. This is an acknowledged problem in NHS services.

If you feel your concerns are not being taken seriously, you can ask for a second opinion. You can also contact your local Child and Adolescent Mental Health Services (CAMHS) or ask your health visitor about community autism support services in your area. The National Autistic Society helpline (0808 800 4104) can advise on local services and what to expect from the assessment process.

You do not need a diagnosis to start support

Formal diagnosis can take a long time. Support does not have to wait.

Speech and language therapy can be requested or self-referred in many areas immediately, and NICE NG142 is clear that it should not wait for an autism diagnosis. If your child has limited speech, limited pointing, or limited response to their name, a speech and language therapist can start working with them now, regardless of what any future assessment finds.

Occupational therapy for sensory differences, Portage (a home visiting educational support service for young children with additional needs), and early years special educational needs support through your local authority are all available before a formal diagnosis. Ask your health visitor what is available in your area and how to access it.

In the meantime, some practical things tend to help many autistic toddlers before anything else is in place. Giving advance notice before transitions ("In five minutes we are going to put the toys away"). Using visual schedules or simple pictures alongside words. Reducing background noise when you want to communicate. Not insisting on eye contact. Following their lead in play. These are not diagnostic tools. They are just warm, respectful ways to help a child who is finding the world a lot to process.

Log what you are noticing, day by day

Cubby lets you record observations and keep a clear timeline to share with your GP, health visitor or developmental specialist.

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Frequently asked questions

What are the earliest signs of autism in toddlers?

Some signs that may be worth discussing with a professional include: not pointing to share interest by 14 months, not waving or imitating gestures by 12 months, no babbling by 12 months, no single words by 16 months, no two-word phrases by 24 months, limited or inconsistent response to their own name, loss of language or skills they had previously, limited interest in other children, and unusual responses to sensory experiences. These signs do not confirm autism. Many appear in children who are not autistic. Only a specialist assessment can give you a clear picture.

Can I tell if my toddler is autistic?

You cannot and should not try to diagnose your toddler yourself, and neither should anyone else without a proper specialist assessment. What you can do is notice patterns over time and share specific, observed concerns with your GP or health visitor. The more concrete your observations, the more useful they are. NICE NG142 recommends that any concerns about possible autism should be taken seriously and referred for specialist assessment.

Does hand flapping mean my toddler has autism?

Not on its own. Repetitive movements like hand flapping, rocking, or spinning appear in many children, autistic and not. In autistic children they serve as a form of self-regulation and are not harmful. Taken alone, they are not a reliable indicator of autism. What matters most is the whole picture: how your child communicates, responds to others, and navigates their world. If you are noticing several differences together, that is worth discussing with your GP rather than any single sign in isolation.

How do I ask for an autism assessment for my toddler?

Speak to your GP or health visitor and share your specific observations. Be as concrete as you can: "She has never pointed at things to show me" is more useful than "I am worried about her development." In the UK, NICE NG142 recommends that GPs refer children with possible autism for a diagnostic assessment. Waiting times vary significantly by area and can be long, so it is better to raise concerns early rather than waiting.

Why does early support matter for autistic toddlers?

The toddler years are a period of very high brain plasticity, meaning the brain is especially responsive to experience and support. Early speech and language therapy, occupational therapy, and ASD-specific early intervention during this window have been shown to make a meaningful difference to outcomes. Early support is not about trying to change who your child is. It is about helping them communicate, understand the world, and be understood, on their own terms.

What should I do while waiting for an autism assessment?

You do not need to wait for a formal diagnosis to access support. Speech and language therapy can start immediately and is recommended by NICE NG142 regardless of whether a diagnosis has been made. Occupational therapy for sensory differences can also start before diagnosis. Ask your GP or health visitor about local early years support, Portage services, and family support programmes. The National Autistic Society (autism.org.uk) has resources and a helpline for families at any stage.