How many people have ADHD

Population prevalence and recorded prevalence are far apart, and the gap between them is the clearest available explanation of why the queue keeps growing.

The short version

The Taskforce describes ADHD as affecting 3 to 5% of the population after a high-quality assessment.
Meta-analyses suggest around 3 to 5% in children and 2 to 3% in adults.
English health records show an administrative prevalence of 2.55% in boys, 0.67% in girls, 0.74% in men and 0.20% in women.
NHS England states that around 1 in 20 children are estimated to be impacted by ADHD globally.

Prevalence numbers are usually quoted to make a point about whether ADHD is over-diagnosed. The figures the Taskforce assembled point the other way, and they explain something practical about the waiting list.

What the population studies suggest

The Taskforce states that ADHD, defined using diagnostic criteria such as DSM-5, after a high-quality assessment, affects 3 to 5% of the population. It adds that meta-analysis of global studies suggests an ADHD prevalence in children of around 3 to 5%, and that for adults, meta-analyses suggest a global population prevalence of 2 to 3%.

NHS England puts the child figure in rounder terms on its own programme page: around 1 in 20 children are estimated to be impacted by ADHD globally.

What the records show

The Taskforce introduces those figures by noting that English health service records have shown increased recognition of ADHD in both children and adults from 2000 to 2018, and its reading of the gap is that under-recognition of ADHD remains a problem in England.

Administrative prevalence in English health service records, as the Taskforce reports it
Group	Recorded prevalence
Boys	2.55%
Girls	0.67%
Men	0.74%
Women	0.20%

Why the gap matters for the wait

If recorded prevalence sits well below population prevalence, then rising referrals are not evidence that the true number of people with ADHD is growing. They are consistent with a backlog being worked through, which is a queue that grows before it clears.

NHS England's own account of the pressure is compatible with that. It says the number of referrals for ADHD assessments and treatment, as well as the number of prescriptions provided, has increased significantly, that this trend is being seen internationally, and that while local NHS teams have been working hard to increase capacity, including referrals to independent services, waiting lists and times have grown.

What these numbers are not

None of them is a count of people waiting for an assessment. No such national count is published here, because the Taskforce records that there are no national reports on waiting times for adults, and no primary source for a waiting-list total was obtainable when this site was built.

Figures of that kind circulate widely. If you see one, trace it before you use it.

Questions people ask about this

How common is ADHD in the UK?

The independent ADHD Taskforce states that ADHD, defined using diagnostic criteria after a high-quality assessment, affects 3 to 5% of the population, with meta-analyses suggesting around 3 to 5% in children and 2 to 3% in adults. Recorded prevalence in English health records is much lower: 2.55% in boys, 0.67% in girls, 0.74% in men and 0.20% in women.

How many people are waiting for an ADHD assessment?

This site publishes no figure, because it could not read one at source: NHS England Digital publishes a national count of open referrals that may be for an ADHD assessment, and every attempt to open that publication from this build was blocked by a bot check. The widely circulated numbers could not be traced to a primary source either. The publication exists, so go to it directly rather than taking a number from anyone repeating it, this site included. This site cannot tell you how up to date it is, because it never got past the bot check to look. Separately, and this is a different measure, the ADHD taskforce stated in June 2025 that there are no national reports on waiting TIMES for adults.