Autism Assessment London
Private autism (ASD) assessment and diagnosis for children, teenagers and adults at 10 Harley Street. A two-stage assessment for a fixed £1,950, reviewed by a multi-disciplinary team, with a free first consultation.
What an Autism Assessment Involves
Autism is a lifelong difference in how a person communicates, connects with others and experiences the world through their senses. You may also see it called autism spectrum disorder (ASD) or autism spectrum condition (ASC). An autism assessment establishes whether someone meets the diagnostic criteria, and builds a picture of their strengths and the support that would help.
Our London assessment runs in two stages. A pre-assessment interview gathers your developmental history. A validated diagnostic assessment then uses recognised tools such as the ADOS-2 and ADI-R. Our multi-disciplinary team reviews the findings before we confirm an outcome, and you receive a written report written to be useful at home, at school and at work.
Autistic Traits We Look At
Needing sameness and feeling real distress when plans change
Strong reactions to noise, light, smells, textures or crowds
Deep, absorbing interests that hold attention for hours
Repetitive movements or routines that help you feel regulated
Exhaustion or shutdown after a day of masking
Is an Autism Assessment Right for You or Your Child?
Families and adults across London ask us for an autism assessment when:
- A nursery, school or health visitor has suggested a child may be autistic
- Parents want diagnostic evidence alongside a request for an Education, Health and Care needs assessment
- A teenager is struggling with friendships, school refusal or sensory overload
- An adult has recognised autistic traits in themselves, often after a child or relative was diagnosed
- A woman or girl has masked for years and is close to burnout
- Someone has a diagnosis of anxiety or depression that has never fully explained their experience
- An adult wants a formal outcome to support a request for workplace adjustments
NHS Autism Waits and Support in London Schools
NICE guidance says an autism diagnostic assessment should start within three months of referral. Few areas meet that. At the end of March 2026, NHS England recorded 270,701 people with an open referral for suspected autism. The National Autistic Society's analysis of the September 2025 figures found that more than 90% of people with an open referral had already waited longer than 13 weeks.
For London families, school support runs through your local authority. Each of the 33 London local authorities publishes a SEND Local Offer describing what is available. You do not need a diagnosis to ask your council for an Education, Health and Care (EHC) needs assessment, and the council should issue a final plan, where one is agreed, within 20 weeks of the request. A diagnostic report can add clear, specialist evidence to that process.
For adults, autism services are commissioned differently across the city, and waits vary by area. Your GP can tell you the current NHS route where you live.
Child and Adult Autism Assessment in London
Child and Teen Autism Assessment
- For children and young people up to the age of 17
- A calm, unhurried session at our Harley Street clinic
- Play-based and conversational observation using ADOS-2 modules suited to age
- A detailed interview with parents or carers about early development
- Information from school or nursery, with your consent
- A report that schools, SENCOs and councils can use to plan support
- A feedback session for the family, in plain language
Adult Autism Assessment
- For anyone aged 18 or over
- At 10 Harley Street, or online by secure video
- A clinical interview about your life now and your childhood
- Structured tools such as the ADOS-2 and DISCO where appropriate
- An interview with a parent, sibling or partner where possible
- Time to look beneath masking and late-recognised presentations
- Adjustments on the day if you ask for them, such as lower lighting or breaks
Diagnostic Tools and Guidance
Recognised Tools
- ADOS-2, the Autism Diagnostic Observation Schedule
- ADI-R, the Autism Diagnostic Interview, Revised
- DISCO, the Diagnostic Interview for Social and Communication Disorders
- AQ and RAADS-R self-report measures for adults
Standards We Work To
- NICE guideline CG128 for children and young people
- NICE guideline CG142 for adults
- DSM-5-TR and ICD-11 criteria for autism spectrum disorder
- A neurodiversity-affirming view of autistic strengths and needs
Private Autism Assessment Cost in London
The same fixed fee for children and adults, paid in two stages, with no extra charges for the report or feedback.
Autism (ASD) Diagnostic Assessment
Stage 1 pre-assessment interview £450, Stage 2 diagnostic assessment £1,500
£1,950
total, pay in full
or 3 interest-free payments of £650 with Klarna Pay in 3.
Book NowCombined Autism and ADHD Assessment
Both conditions in one pathway
£2,600
pay in full
or £650 a month for 4 months at 0% with PayPal Credit.
Book NowAutism and ADHD often occur together. The combined pathway costs £350 less than booking the two assessments one after the other. If attention and focus are the main concern, see our ADHD assessment in London. Fees for every clinic are on our pricing page.
PayPal Credit is subject to PayPal's own terms, eligibility checks and approval at checkout. It offers 0% interest for the first 4 months on purchases of £99 or more, with the standard variable rate applying to any balance after that. Klarna instalments are interest-free and subject to Klarna's eligibility and affordability checks. 18+ UK residents only. Terms apply.
How to Get an Autism Diagnosis in London
Talk to Us
Book a free consultation. Tell us what you or your child find hard and what you hope an assessment will answer. We confirm the fee before you decide anything.
Pre-Assessment Interview
Your clinician gathers your developmental and family history, and plans the diagnostic session around your needs and any adjustments you would like.
Diagnostic Assessment
Structured observation and interview using validated tools, at a pace that feels comfortable. Children are seen at our Harley Street clinic. Adults can attend in person or online.
Outcome and Report
After a multi-disciplinary review, you receive your written report and a feedback session that explains the outcome and the support that could help.
Visiting Our Harley Street Clinic
Autism and ADHD Diagnostic Centre, London
10 Harley StreetLondon W1G 9PF
Phone: 0141 212 4966
- A short walk from Oxford Circus, Bond Street, Regent's Park and Great Portland Street stations
- Bond Street is on the Elizabeth line, with direct trains from Heathrow, Paddington and Stratford
- Tell us before your visit about any adjustments that would help, such as lower lighting or breaks
- Clients travel from every London borough and the commuter towns beyond
Who Carries Out Your Autism Assessment
Your assessment is carried out by clinicians with long experience of autism, and our multi-disciplinary team reviews every outcome.
Andy Fleming
Neurodevelopmental Clinician, RMN, RNLD, BN, PG Dip Autism
Holds a postgraduate diploma in autism and has practised as a nurse since 1988.
Read full profile
Fiona Ramsay
Neurodevelopmental Clinician, Dip COT
An occupational therapist who has spent 33 years working with people who present with autistic traits.
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Yvonne Samson
Neurodevelopmental Clinician, RNLD, RNA, BSc Professional Health Studies
Over 25 years as a registered nurse, much of it supporting autistic people and people with learning disabilities.
Read full profile
Mary Lynas
Neurodevelopmental Clinician, BSc Hons Occupational Health
Brings 15 years as a qualified therapist and 23 years in learning disability services.
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Margaret Serrels
Service Manager
Leads our service with more than 30 years in mental health and learning disability care.
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Saduf Riaz
Director
A medical graduate of the University of Glasgow with over 22 years in mental health.
Read full profileClinical Regulation
- The Care Quality Commission (CQC) regulates our services in England.
- Every doctor on our team is registered and licensed with the General Medical Council (GMC).
- Our psychiatrists belong to the Royal College of Psychiatrists.
Masking and Late Diagnosis
Masking means copying others or hiding autistic traits to fit in. Many people do it without realising. It can work for years, especially for girls and for adults who did well at school, but it often comes at a cost: exhaustion, anxiety and, for some, burnout.
Because masking hides the signs, autism in women and girls is often recognised late. Our clinicians allow time to understand what lies beneath it, and draw on accounts from people who knew you as a child.
Support After an Autism Diagnosis
A diagnosis opens doors to understanding and support. Your report and feedback session can help with:
- Evidence for an EHC needs assessment or SEN support at a London school
- Reasonable adjustments at work, including sensory and communication changes
- Explaining your needs to family, friends and colleagues
- Finding support through the National Autistic Society, Ambitious about Autism and your council's Local Offer
Autism Assessment London: Your Questions Answered
How long do people wait for an NHS autism assessment?
Much longer than recommended. NICE says an assessment should start within three months of referral, but NHS England recorded 270,701 people with an open suspected autism referral at the end of March 2026, and the National Autistic Society found more than 90% had waited over 13 weeks. Waits in London vary by borough and service.
What does a private autism assessment in London cost?
£1,950 at our Harley Street clinic, the same for children and adults. It is paid in two stages: £450 for the pre-assessment interview and £1,500 for the diagnostic assessment. You can also spread it over 3 interest-free payments of £650 with Klarna. A combined autism and ADHD assessment costs £2,600.
Which tools do you use to diagnose autism?
We use recognised diagnostic tools such as the ADOS-2, ADI-R and DISCO, chosen to suit the person's age and needs, alongside a developmental history. We follow NICE guidelines CG128 and CG142 and the DSM-5-TR and ICD-11 criteria.
Can an adult be assessed for autism?
Yes. Adults of any age can be assessed, and many come to us in their thirties, forties or later. Adults can attend our Harley Street clinic or have the assessment online by secure video.
Why is autism in women and girls often missed?
Many women and girls mask their traits, and their autism can look different from the patterns people expect. Teachers and doctors may therefore miss it. Our clinicians take time to look beneath masking and ask about early childhood.
How old does a child need to be for an autism assessment?
There is no single minimum age. We assess children and young people up to 17, and choose observation activities that suit their age and stage of development. Your free consultation confirms whether an assessment is appropriate now.
Does my child need a diagnosis to get an EHCP?
No. You can ask your local authority for an EHC needs assessment without a diagnosis. A diagnostic report can still add useful evidence. The council makes its own decision, and should issue any final plan within 20 weeks of the request.
Will the NHS recognise a private autism diagnosis?
You can give your report to your GP to add to your records. GP practices and NHS services each decide how they use a private report, so ask your practice about its approach before you start.
Is Asperger's still diagnosed?
No. Asperger's syndrome is no longer a separate diagnosis. It now falls under autism spectrum disorder in both DSM-5-TR and ICD-11. Some people who received an Asperger's diagnosis still prefer to use that term.
What happens after an autism diagnosis?
You receive a written report with personalised recommendations and a feedback session to talk it through. We point you to organisations such as the National Autistic Society and Ambitious about Autism, and to your council's Local Offer.
Book an Autism Assessment in London
Start with a free consultation. We listen to what you have noticed, explain each stage, and help you decide whether an assessment is the right step for you or your child.
Book a Free Consultation