Types of Autism: DSM-5 Levels & Former Subtypes Explained

Under the current Diagnostic and Statistical Manual (DSM-5, published 2013, with a text revision in 2022 known as DSM-5-TR), there is a single autism diagnosis — autism spectrum disorder (ASD) — described by three support levels (Level 1, Level 2, Level 3) and by specifiers such as with or without accompanying intellectual or language impairment. The older labels (autistic disorder, Asperger’s syndrome, PDD-NOS, childhood disintegrative disorder) were folded into ASD, and Rett syndrome is a separate genetic condition — not a type of autism.

Is There More Than One Type of Autism?

In the current system, no — there is one autism diagnosis. Autism is now classified as a single condition on a spectrum (autism spectrum disorder, or ASD), not as a set of separate “types.” What used to be labelled as different diagnoses — autistic disorder, Asperger’s syndrome, PDD-NOS, and childhood disintegrative disorder — were consolidated into ASD when the DSM-5 was published in 2013.

What varies from one autistic person to the next isn’t the diagnosis — it’s the level of support they need, their language and cognitive profile, their sensory experience, their strengths, and whether other conditions are present alongside autism. The DSM-5 and DSM-5-TR describe this variation through three support levels and a short list of specifiers, which are covered in the next two sections.

Rett syndrome, which was once sometimes grouped with autism, is a separate genetic condition and is addressed later in this article.

The 3 Levels of Autism (DSM-5)

The DSM-5 and DSM-5-TR describe three levels of autism based on how much support a person needs in daily life. The levels aren’t categories a person moves between arbitrarily — they’re a clinical shorthand for how much structure, accommodation, or hands-on support a person requires to function in a given setting at a given point in their life.

At-a-Glance: ASD Support Levels

Level	Support needed	Social communication	Restricted or repetitive behaviours
Level 1	Requiring support	Noticeable difficulties in social communication without supports in place; may appear uninterested in social interactions or respond atypically	Inflexibility of behaviour that causes significant interference with functioning; difficulty switching between activities; problems with organization and planning
Level 2	Requiring substantial support	Marked deficits in verbal and nonverbal social communication; social impairments apparent even with supports; limited initiation of social interactions and reduced or atypical responses to others	Inflexibility of behaviour, difficulty coping with change, or other restricted/repetitive behaviours appearing frequently enough to be obvious to an observer and to interfere with functioning in several contexts
Level 3	Requiring very substantial support	Severe deficits in verbal and nonverbal social communication cause severe impairments in functioning; very limited initiation of social interactions and minimal response to social overtures from others	Inflexibility of behaviour, extreme difficulty coping with change, or other restricted/repetitive behaviours markedly interfering with functioning across all areas; great distress or difficulty changing focus or action

For a deeper look at what Level 1 autism actually looks like in adulthood, see Level 1 autism and independent living.

A support level isn’t a fixed judgment about ability. It’s a snapshot — and it can change over time with therapy, maturity, and environment. For a specific breakdown of which autism levels benefit from ABA and what the therapy looks like at each level, that article walks through the clinical thinking.

Level 1: Requiring Support

Children and adults at Level 1 can communicate verbally and often appear socially engaged. The challenges typically show up in subtler ways: difficulty initiating social interactions, atypical responses to overtures from others, inflexibility that interferes with daily functioning, and problems with planning and organization. People at Level 1 often live independently, work, and form relationships, with specific accommodations and support in place where needed.

Level 2: Requiring Substantial Support

At Level 2, difficulties with verbal and nonverbal social communication are more pronounced and visible even when the person is receiving support. Social interactions are often limited, and restricted or repetitive behaviours are frequent enough to be obvious to anyone observing. Daily functioning often requires meaningful structure and support across multiple settings.

Level 3: Requiring Very Substantial Support

At Level 3, severe deficits in both verbal and nonverbal communication, very limited initiation of interaction, and extreme behavioural inflexibility have a major impact on daily functioning. Many people at Level 3 require very substantial and often around-the-clock support.

The 2013 DSM-5 consolidation changed how clinicians describe all the types of autism that had existed as separate labels under the previous manual, folding them into a single diagnosis with support levels and specifiers.

Types Of Autism | Special Education Decoded

DSM-5 Specifiers

In addition to assigning a support level, a clinician diagnosing autism spectrum disorder adds specifiers to describe the fuller clinical picture. These specifiers aren’t optional add-ons — they’re part of a complete diagnosis and shape what support looks like.

The specifiers include:

With or without accompanying intellectual impairment
With or without accompanying language impairment
Associated with a known medical or genetic condition or environmental factor (for example, autism co-occurring with Fragile X syndrome or tuberous sclerosis)
Associated with another neurodevelopmental, mental, or behavioural disorder (for example, autism co-occurring with ADHD or an anxiety disorder)
With catatonia

A person diagnosed with ASD Level 1 without intellectual impairment and without language impairment looks very different, clinically, from a person diagnosed with ASD Level 3 with accompanying intellectual impairment and a known genetic condition. The specifiers are what carry that difference, and they inform the direction of therapy and support.

Former Autism Subtypes (Used Before 2013)

Before the DSM-5 was published in 2013, autism was classified as several separate diagnoses. Those labels still appear in older records, in media coverage, and in some conversations — so it’s worth knowing what each one meant and how the same person would be diagnosed today.

1. Autistic Disorder (“Classic Autism”)

Autistic disorder, sometimes called classic or Kanner’s autism, was the historical core autism diagnosis under the DSM-IV. It was given to children and adults with substantial challenges in social communication, repetitive behaviours, and often with co-occurring intellectual or language differences. Today, someone who would previously have been diagnosed with autistic disorder is diagnosed with autism spectrum disorder, with a support level (often Level 2 or Level 3) and the relevant specifiers.

2. Asperger’s Syndrome

Asperger’s syndrome was first described by Hans Asperger in 1944 and was a separate diagnosis under the DSM-IV for people with social communication and interaction differences who did not have an intellectual disability or an early language delay. The DSM-5 retired the Asperger’s diagnosis in 2013 and folded it into ASD. For a fuller account of why the retired labels went away and what replaced them, see our article on why “high-functioning” and Asperger’s labels were retired.

Today, someone who would previously have received an Asperger’s diagnosis is usually diagnosed with ASD, often at Level 1, with the specifiers “without accompanying intellectual impairment” and “without accompanying language impairment.”

3. Pervasive Developmental Disorder — Not Otherwise Specified (PDD-NOS)

PDD-NOS was a DSM-IV diagnosis used for people who showed autism-like traits but did not meet the full criteria for autistic disorder, Asperger’s, or Rett syndrome. It was effectively a catch-all for presentations that didn’t fit the other labels. Today, someone who would previously have received a PDD-NOS diagnosis is diagnosed with autism spectrum disorder with a support level — often Level 1.

4. Childhood Disintegrative Disorder (CDD)

Childhood disintegrative disorder, sometimes called Heller’s syndrome after Austrian educator Theodor Heller who first described it in 1908, was a rare DSM-IV diagnosis given to children who developed typically for at least their first two years before losing significant previously acquired skills — in language, social function, motor skills, bowel or bladder control, or play — before age 10.

CDD is not the same as “regressive autism.” Regressive autism is a term used to describe loss of previously acquired skills that can occur in autism more broadly, usually in toddlerhood. CDD, as defined in the DSM-IV, involved longer periods of typical development followed by more extensive and later regression. The DSM-5 retired CDD as a separate diagnosis in 2013. Today, a child who would previously have received a CDD diagnosis would be diagnosed with autism spectrum disorder, with the clinical history of regression documented as part of the overall picture.

(Chevi: verify the CDD onset ages above against the DSM-IV-TR criteria before publishing — the current page says “two to four,” but DSM-IV-TR allowed regression any time after at least two years of typical development through age 10. The language above reflects the broader DSM-IV-TR range.)

5. Rett Syndrome (A Separate Genetic Condition)

Rett syndrome is not a type of autism and was not an autism diagnosis under the DSM-IV either, though it was sometimes grouped with autism in older frameworks. It is a rare neurodevelopmental genetic disorder caused primarily by mutations in the MECP2 gene on the X chromosome. It occurs almost entirely in people assigned female at birth; in males, the condition is typically lethal before or shortly after birth because they have only one X chromosome.

Children with Rett syndrome usually develop typically for the first several months of life before entering a period of regression, often beginning between 6 and 18 months, with loss of purposeful hand use, loss of acquired speech, and the appearance of stereotypic hand movements such as hand wringing. Diagnosis is confirmed through genetic testing. Rett syndrome is diagnosed and managed as its own condition, not as autism.

(Chevi: verify the Rett syndrome genetic and onset details against NIH / NINDS or the International Rett Syndrome Foundation before publishing. The MECP2 gene identification and X-linked inheritance are well-established, but double-check the onset-age window.)

Former label	Status today	How it’s described now
Autistic disorder (also known as classic autism or Kanner’s autism)	Retired in DSM-5 (2013); folded into ASD	Diagnosed as autism spectrum disorder (ASD) with a support level and specifiers
Asperger’s syndrome	Retired in DSM-5 (2013); folded into ASD	Usually diagnosed as ASD Level 1, with the specifier “without accompanying intellectual or language impairment”
PDD-NOS (Pervasive Developmental Disorder — Not Otherwise Specified)	Retired in DSM-5 (2013); folded into ASD	Diagnosed as ASD with a support level — often Level 1
Childhood Disintegrative Disorder (CDD)	Retired in DSM-5 (2013); folded into ASD	Diagnosed as ASD, with the clinical history of regression documented in the overall picture
Rett syndrome	Separate genetic condition — not a type of autism	Diagnosed via genetic testing (MECP2 gene) and managed as its own neurodevelopmental disorder

Conditions Sometimes Confused With Autism

Several other conditions share surface features with autism and can be mistaken for it, especially early in life. Two are worth knowing about:

Social (pragmatic) communication disorder (SPCD) is a diagnosis for people with persistent difficulties in the social use of language — reading social cues, taking turns in conversation, adjusting language for context — without the restricted and repetitive behaviours required for an autism diagnosis. For a fuller comparison, see social communication disorder vs. autism.
Sensory processing disorder (SPD) describes significant difficulty processing sensory input — touch, sound, movement — without the social communication differences that define autism. Sensory differences are common within autism, but SPD is a separate concept. See autism vs. sensory processing disorder for more.

A thorough diagnostic evaluation by a qualified clinician is the only reliable way to tell these apart.

Conclusion

The way autism is classified has changed meaningfully over the last decade. There is now one diagnosis — autism spectrum disorder — described by support level and by specifiers that reflect the full clinical picture. Older labels like Asperger’s syndrome, PDD-NOS, and childhood disintegrative disorder haven’t been “deleted”; they’ve been consolidated into ASD so clinicians can describe variation more precisely. Rett syndrome, which was sometimes grouped with autism in older frameworks, is a separate genetic condition.

If you or someone in your family is wondering whether to pursue an evaluation, a thorough diagnostic process is the only reliable way to answer the question. Learn more about autism evaluation at Epic Minds Therapy, or reach out to our team to talk through next steps.

Frequently Asked Questions

What are the 3 levels of autism?

The DSM-5 describes three support levels for autism spectrum disorder. Level 1 (requiring support) describes autistic people who have noticeable social communication challenges and benefit from specific supports, but who often live and work independently. Level 2 (requiring substantial support) describes marked difficulties in verbal and nonverbal social communication that are apparent even with supports in place. Level 3 (requiring very substantial support) describes severe social communication challenges and significant inflexibility that have a major impact on daily functioning. A person’s level is a snapshot in time, not a fixed judgment, and it can shift with therapy, maturity, and environment.

Are there 7 types of autism?

No — there is no official 7-type classification of autism in the current diagnostic manual. The DSM-5 recognizes one autism diagnosis (autism spectrum disorder) with three support levels and a set of specifiers. The “7 types” idea sometimes seen online appears to be either a mix of retired DSM-IV labels, informal categories, or confusion with unrelated frameworks. If a healthcare professional uses the term, ask them which classification system they’re referring to.

Is Asperger’s still a diagnosis?

Not in the DSM-5 or DSM-5-TR. Asperger’s syndrome was retired as a separate diagnosis in 2013 and folded into autism spectrum disorder. People who would previously have received an Asperger’s diagnosis are now usually diagnosed with ASD Level 1, with the specifiers “without accompanying intellectual impairment” and “without accompanying language impairment.” People who were diagnosed with Asperger’s before 2013 keep that record, and many still identify with the term.

What are the different types of autism?

Under the current DSM-5 and DSM-5-TR, there is one autism diagnosis — autism spectrum disorder (ASD) — described by three support levels (Level 1, 2, and 3) and by specifiers such as with or without accompanying intellectual or language impairment. Older labels like Asperger’s syndrome, PDD-NOS, and childhood disintegrative disorder were retired in 2013 and folded into ASD. Rett syndrome is a separate genetic condition and is not a type of autism.

What does “on the spectrum” mean?

“On the spectrum” refers to the fact that autism is diagnosed as a single spectrum condition — autism spectrum disorder — with wide variation in how it shows up from one person to the next. Being “on the spectrum” means a clinician has diagnosed the person with ASD; it does not say anything specific about their support needs, cognitive profile, or language ability without further information. For a fuller explanation, see what it means to be on the spectrum.

Can adults be diagnosed with autism later in life?

Adults can get an autism diagnosis. This often happens through a careful check by doctors who know about autism. The diagnostic process looks for different symptoms. These can show up in social skills, the way people talk to others, or how they behave. The American Psychiatric Association says that, even if there are only some mild signs, people can be checked for autism later in life. These checks are for all, as the signs can change as people get older.

Is there a cure for autism?

There is no way to cure autism for good. But, there are some helpful treatment options. These can include therapies and sometimes medicine. They help people improve their quality of life. The medical community works hard to manage symptoms. They do this by using ways to help people live better every day. This support helps make life more open and easy for people with ASD over the years.