Get assessed
ADHD assessment UK: how to get diagnosed
In the UK there are three main routes to an adult ADHD assessment: a standard NHS referral through your GP, NHS Right to Choose in England (where you can ask to be referred to an approved provider, still free on the NHS), or paying for a private assessment. All three end in an assessment by a qualified clinician. This is information, not medical advice, and only a clinician can diagnose ADHD.
Information only. This page explains how the routes work. It is not medical advice and not a diagnosis. Only a registered clinician can assess and diagnose ADHD.
The three routes, in plain English
Most adults in the UK reach an ADHD assessment in one of three ways. Each ends with an assessment by a suitably qualified clinician. The difference is who pays and how long you tend to wait.
- Standard NHS referral. You speak to your GP, who can refer you to the local NHS ADHD service. It is free, but waiting times can be long in many areas.
- NHS Right to Choose (England). In England you have a legal right to choose which provider your GP refers you to for many services, including some ADHD assessments. It is still free on the NHS, and can sometimes be quicker. We explain it in detail in Right to Choose ADHD assessment explained.
- Private assessment. You pay a private provider, often with self-referral and a shorter wait. Costs vary. See how much a private ADHD assessment costs.
What an assessment involves
An ADHD assessment is more than a quick questionnaire. A clinician typically reviews your history from childhood to now, your current difficulties, and how symptoms affect daily life. They may use structured tools and, where possible, information from someone who knew you growing up. The aim is a careful clinical judgement, not a single test score.
The National Institute for Health and Care Excellence (NICE) sets out how ADHD should be diagnosed and managed in its guideline NG87. The Royal College of Psychiatrists also publishes guidance for clinicians. These set the standard a good assessment should meet.
How to choose your route
If cost is the main concern, the NHS and Right to Choose routes are free. If waiting time is the main concern, Right to Choose or a private assessment may be faster, though this varies by provider and area. Our comparison of NHS vs private ADHD assessment lays out the trade-offs side by side, and our guide to ADHD assessment waiting times covers what to expect.
Whichever route you take, it helps to know what to look for in a provider so you can be confident the assessment is carried out properly. To weigh the routes side by side, see all our comparison pages, and before you book, our guide on how to prepare for an ADHD assessment covers what to bring.
Frequently asked questions
Do I need a referral for an ADHD assessment?
For an NHS assessment, including the NHS Right to Choose route in England, you usually start by speaking to your GP, who can make a referral. Most private providers accept self-referral, so you can book directly. Your GP can confirm what applies in your area.
Can I be assessed for ADHD as an adult?
Yes. Adults can be assessed for ADHD. Many people are diagnosed in adulthood. An assessment is carried out by a suitably qualified clinician, such as a psychiatrist or a specialist ADHD practitioner.
How long does an ADHD assessment take?
The assessment appointment itself is often a single session of around one to three hours, sometimes split across visits. The wait to reach that appointment varies widely by route and area. We cover waiting times in a separate guide.
Is an online ADHD assessment valid?
A remote assessment can be valid when it is carried out by a suitably qualified UK clinician following recognised guidance. What matters is the clinician's qualifications and process, not whether it is in person or online. Check the provider before you book.
Editor, ADHD Helper
Oliver leads ADHD Helper's editorial coverage of adult ADHD. He researches and writes the plain-English explainers on getting an ADHD assessment through NHS Right to Choose or privately, and on the products and tools people use to manage ADHD, drawing on guidance from the NHS, NICE and the Royal College of Psychiatrists. He is clear that the site is information, not medical advice, and that diagnosis is for a registered clinician.
Last reviewed: 8 June 2026