People have often used the terms “high functioning autism” and “low functioning autism” to describe how independently an Autistic person appears to manage daily life.
These descriptions may sound simple and convenient, but they are not formal diagnoses. They can also create an inaccurate picture of a person’s abilities, difficulties and support needs.
Autism is a spectrum, but it is not a straight line that runs from “less Autistic” to “more Autistic.” Each Autistic person has a different combination of strengths, communication preferences, sensory experiences and support requirements.
This is why the language we use matters.
What Does “High Functioning Autism” Mean?
The term “high functioning” has commonly been used to describe an Autistic person who speaks fluently, has average or above average intelligence, completes academic work or manages some daily activities independently.
However, these visible abilities do not show everything the person may be experiencing.
Someone described as high functioning might still experience:
- Significant sensory overload
- Difficulty managing changes and uncertainty
- Exhaustion from masking
- Anxiety or depression
- Difficulty organising daily responsibilities
- Challenges recognising or communicating personal needs
- Emotional regulation difficulties
- Autistic burnout
- A need for substantial support in unfamiliar environments
A child may perform well academically but be unable to manage the sensory and social demands of school without becoming distressed at home.
An adult may have a successful career while struggling with eating, personal care, household tasks or maintaining relationships.
Calling the person high functioning may cause others to underestimate these needs. It can create an expectation that the person should cope independently because they appear capable in certain areas.
What Does “Low Functioning Autism” Mean?
The term “low functioning” has commonly been used for Autistic people who have limited spoken language, intellectual disability, significant daily living needs or behaviours that create safety concerns.
This label can also be misleading.
A person who does not communicate through speech may still understand more than other people realise. They may communicate through gestures, signs, pictures, typing, facial expressions, behaviour or an augmentative and alternative communication device.
They may also have meaningful relationships, personal preferences, humour, creativity and the ability to make choices when information and communication are made accessible.
Describing someone as low functioning can cause people to underestimate their understanding and potential. It may lead others to speak about the person rather than to them, exclude them from decisions or provide fewer opportunities to learn.
A need for extensive assistance does not remove a person’s capacity to express preferences, participate in relationships or enjoy a meaningful life.
What Terms Are Used in Diagnosis?
The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision, known as the DSM 5 TR, does not diagnose people as having high functioning or low functioning autism.
Instead, it describes three support levels:
- Level 1 means requiring support
- Level 2 means requiring substantial support
- Level 3 means requiring very substantial support
These levels are considered separately across two areas:
- Social communication and social interaction
- Restricted or repetitive patterns, including flexibility, routines, interests and sensory experiences
A person may have different support levels across these areas. For example, someone may require support with social communication but substantial support with change, sensory regulation and daily routines.
The support levels can provide useful clinical information, but they still do not describe the whole person.
Are Support Levels the Same as Functioning Labels?
Support levels should not simply be treated as replacements for high functioning and low functioning labels.
They describe the amount of support a clinician believes the person requires at the time of assessment. They do not measure intelligence, personality, empathy, future potential or the value of the person’s life.
Support needs may also change according to:
- The environment
- The activity being completed
- Familiarity with the people present
- Sensory demands
- Physical health
- Mental health
- Communication access
- Stress and fatigue
- Major life changes
- The quality of available support
An Autistic person might require minimal assistance in a quiet and familiar environment but substantial support in a noisy, unpredictable or socially demanding setting.
The person has not suddenly become more or less Autistic. The demands of the environment and the support available have changed.
Why Do Functioning Labels Matter?
The words used to describe a person can influence how other people treat them.
Calling someone high functioning may result in their struggles being dismissed. They might be denied adjustments, criticised for asking for help or expected to maintain an exhausting level of masking.
Calling someone low functioning may cause others to focus only on limitations. Their communication may be ignored, their choices may not be respected and their opportunities may be unnecessarily restricted.
Both labels reduce a complex person to a broad judgement.
They can also create an unhelpful divide within the Autistic community by suggesting that some people are successful and capable while others are not.
A Better Way to Describe Support Needs
Rather than assigning a general functioning label, it is more helpful to describe the person’s actual strengths and needs.
For example, we could say:
- “She communicates verbally but needs support to recognise and manage sensory overload.”
- “He uses a communication device and requires assistance with personal care.”
- “They work independently but need clear written instructions and advance notice of changes.”
- “She understands spoken language but communicates most effectively through pictures and gestures.”
- “He requires close supervision in the community because he has limited awareness of danger.”
These descriptions provide practical information. They tell families, educators and practitioners what support may help without making a broad judgement about the person’s overall ability.
It is also important to ask the Autistic person which language they prefer whenever possible. Some people prefer identity first language, such as “Autistic person,” while others prefer person first language, such as “person with autism.”
Focus on the Person, Not the Label
Two people with the same autism support level may have very different lives, abilities and goals. Support should therefore be based on an individual assessment rather than the diagnostic level alone.
Helpful planning considers:
- How the person communicates
- What activities are meaningful to them
- What causes distress or creates barriers
- What helps them feel regulated and safe
- Which daily activities require assistance
- What they can do independently
- What choices and goals matter to them
- How their environment can be adjusted
The purpose of assessment should be to understand the person and arrange appropriate support. It should not be to decide how capable or valuable they are.
Does It Matter?
Yes, it matters because language shapes expectations.
The terms high functioning and low functioning can hide important support needs, underestimate abilities and oversimplify the varied ways autism affects daily life.
A more respectful and accurate approach is to describe the individual’s specific strengths, communication preferences and support requirements. These needs may change across environments and over time.
An Autistic person should never have to appear distressed enough to receive support or independent enough to be treated with dignity.
Every person deserves to have their abilities recognised, their communication respected and their support based on what they genuinely need to participate in everyday life.
Sources
Autism CRC: National Guideline for the Assessment and Diagnosis of Autism in Australia
Australian Government: National Autism Strategy 2025 to 2031
National Autistic Society: What Is Autism?
American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders
