As of December 2025, there were 254,108 patients with an open referral for suspected autism, latest NHS data has revealed.

Nine in Ten (228,983/90.1%) have been waiting, longer than the 13 weeks for an assessment recommend by the National Institute for Health and Care Excellence (NICE).

This data shows that while the number of people waiting is levelling out, the time people are waiting for an assessment is rocketing.

The NAS is calling on the Government to urgently address the growing autism diagnosis crisis and to immediately provide dedicated funding for diagnosis services.
 

Too many waiting too long

An autism diagnosis is vital to getting the right help and support. An autism assessment can be the first step to understanding people’s needs and although they shouldn’t be, people are often told they can’t get support without a diagnosis. Without a diagnosis many people struggle at school, work or home, develop mental health problems like anxiety or depression - and in some cases end up in crisis or even in hospital.
 

Government must act

The diagnosis process for autism in a modernised NHS that is fit for the future must be timely and use a standardised process for assessments that meet NICE guidelines. NHSE published the Autism Assessment Framework and Operational Guidance three years ago to reinforce standards for assessment. However, ICBs are not able to follow the framework due to a lack of funding in the workforce and in recruitment. Dedicated funding is needed to establish this standardised process and bring down waiting times
 

Our Response

Mel Merritt, Head of Policy and Campaigns at the National Autistic Society, said: “There are over 254,000 people on the waiting list for an autism assessment – that’s more than the population of Southampton. NHS guidelines state people shouldn’t be waiting more than three months for an initial assessment, yet 90% of people have been waiting longer than this.

Getting an assessment shouldn’t be this hard. Waiting this long puts people at risk. A new report from Bournemouth University highlights that quick access to diagnoses is needed to reduce the risk of suicide. The report included 4,000 responses, from autistic people who had suicidal thoughts and families/carers bereaved by the suicide of an autistic person, and shows how crucial a diagnosis and tailored support is for autistic people.

Yet there’s a lack of Government action. The NHS 10-year plan has no mention of autism, and the Government has yet to start developing a new autism strategy. This study should serve as a wakeup call, especially as waiting times are rocketing.

Autistic people and their families face a constant fight for support and this often starts with long waits for a diagnosis. The Government must provide urgent funding for diagnosis services to end this worsening crisis, and make sure autistic people and families get the support they need when they need it.”