What Is Level 3 Autism?

What does level 3 autism mean?

Autism diagnoses in Australia include a support level, and level 3 is the highest of the three levels used in the DSM-5-TR (Raising Children Network).

• Level 1 means the person needs support, level 2 means they need substantial support, and level 3 means they need very substantial support.
• The level describes how much support a person needs, not how capable, intelligent or valued they are as an individual.
• The level is set separately for social communication and for repetitive behaviours, special interests or sensory differences, so a person can sit at different levels in each area.
• Support levels can change over time, so a level recorded in childhood may be reviewed as a person grows and their supports change.

If you are comparing the levels, read our guides to level 2 autism and level 1 autism.

Level 3 ASD meaning and other names for it

See also the types of autism and the autism definition.

Level 3 autism symptoms and support

The Autism Association of Australia describes level 3 as “requiring very substantial support”, and every autistic person is different (Autism Association of Australia).

• A person may have severe difficulties with communication and may be nonverbal, so they may use pictures, signs, devices or other ways to communicate.
• The person may rely heavily on others for daily activities.
• Sensory differences and repetitive behaviours are one of the two areas a support level describes; ask the person’s clinician what supports suit them.
• Strengths and interests are part of the picture too, and support plans can include what the person enjoys and does well.

These descriptions are not a checklist, and only a qualified professional can assess any person. Our guides to PDA autism and severe autism explain related terms.

TQN Care support workers help with personal care, community access, respite and help around the home across Sydney, Melbourne and surrounding areas (NSW & VIC). Tell us what you need and we will call you back.

Level 3 autism in toddlers

A toddler does not usually have a level recorded until a specialist has completed a full assessment.

1. 1Talk to your GP or child health nurse. Raise any concerns about your toddler’s communication, play or response to sound and touch.
2. 2Ask for a referral. Your GP can explain which specialists assess young children for autism near you and whether there are waiting lists.
3. 3Keep a short daily diary. Note what your toddler does, what helps and what is hard, and bring it to appointments.
4. 4Ask about early support. Ask your GP what early support is available while an assessment is arranged.

Level 3 autism in adults

Adults at this level may rely heavily on others for daily activities, so it helps to plan support around the person’s own goals.

• Plan support around the person’s goals, such as time with friends, activities in the community, work or volunteering, or learning daily living tasks.
• Ask about personal care, meal preparation and household help.
• Use communication supports that the person already responds to, and share them with every new support worker before the first shift.
• Look at the person’s living situation as they get older, including support at home, shared living options and respite for family carers.

Our guide to disability support worker levels explains how the roles differ.

Level 3 autism life expectancy

Outcomes vary, and a doctor who knows the person is the right source.

An Autism CRC study of autistic people in NSW, aged 5 to 64 between 2001 and 2015, found autistic people had double the comparative mortality rate of the general population (Autism CRC).

What did the study find about causes?

The study found the most common causes were injury or poisoning, including accident and suicide, followed by nervous system disorders such as epilepsy. It looked at autistic people overall, so it does not give a figure for level 3.

• Ask your GP about regular health checks and how to manage conditions such as epilepsy.
• Talk with your support team about home safety, supervision during community outings and water and road safety.
• Seek mental health support early, and ask your GP or specialist about services that understand autistic people.
• If you or someone you know is struggling, call Lifeline on 13 11 14, and call 000 if someone is in immediate danger.

Level 3 autism under the NDIS

If you meet the NDIS access requirements, this diagnosis can help show you qualify.

• The NDIA’s Applying to the NDIS guideline (26 August 2026) lists autism diagnosed at level 2 or level 3 on List A (NDIA).
• The diagnosis must come from a specialist multi-disciplinary team, paediatrician, psychiatrist or clinical psychologist using current DSM criteria.
• Bring the diagnostic report and therapy reports to your planning meeting, along with a list of the daily supports the person needs.
• Read our guide to autism funding under the NDIS for how plans and evidence work.

When to talk to a GP or specialist

• You are worried about your child’s communication, play or development and would like an assessment or a referral.
• The person’s support needs have changed, and you want to ask whether their support level should be reviewed.
• You notice changes in sleep, eating, mood or seizures, or the person seems to be in pain but cannot tell you.
• You are a carer feeling exhausted, and you want to talk about respite and your own wellbeing.
• You would like free information or a listening ear, and you can call Autism Connect on 1300 308 699 (Amaze).

Call 000 in an emergency.

TQN Care support workers help with personal care, community access, respite and help around the home across Sydney, Melbourne and surrounding areas (NSW & VIC). Tell us what you need and we will call you back.

Your next step

If you or someone you care for is autistic, practical help from a support worker may suit your needs. We help with personal care, community access, respite and help at home, and you can see our full range on our NDIS services page. Tell us what matters to the person and we will suggest how we can help.