How Long Does an ADHD or Autism Assessment Take? My 20-Month Wait — and the NHS Route That Took 10 Weeks

I waited twenty months for an ADHD assessment that never came. Then I made one phone call, learned one thing about how NHS funding actually works, sent my GP one polite request — and was diagnosed ten weeks later.

This is the article I wish someone had handed me at month one. It's my own story, the mechanism behind it, and the exact steps — including the email template — so you can skip the part where you lose nearly two years to a queue that was never going to move.

The short version

If you're in England and your GP refers you for an ADHD or autism assessment, you have a legal right to choose which provider that referral goes to — including independent providers who hold NHS contracts and run dramatically shorter waiting lists. It's called Right to Choose, it's still NHS-funded, it costs you nothing, and most people have simply never heard of it.

I hadn't either. Here's how I found out.

My twenty months in the queue

When I first spoke to my GP about an ADHD assessment, the process felt reassuringly normal: a chat, a couple of screening questionnaires, a referral to the local assessment service. Job done, I thought. You wait a bit, you get seen.

You wait more than a bit. Months passed. Then a year. The letters didn't come. And the thing about waiting for an assessment is that you're not just waiting for an appointment — you're waiting for an explanation of your entire life, while continuing to live the unexplained version of it. Every chaotic week came with a little voice saying *maybe the assessment will sort this* — except the assessment was a rumour with a reference number.

At the twenty-month mark, I did the thing I should have done at month three: I rang the clinic that was supposed to be seeing me and asked, plainly, where I was in the queue and why it was taking so long.

The person I spoke to was honest with me, and what they explained changed everything.

"It's not the appointments. It's the funding pot."

What the clinic explained to me — and I'm recounting their explanation, because it was the key that unlocked everything — was that the wait depends on which pathway your referral travels down, because different pathways are funded differently.

The standard GP referral route I'd taken was drawing on a limited local funding arrangement — a small pot. The clinic wasn't short of assessors or appointment slots so much as it was rationing a constrained budget across a very long queue. Twenty months wasn't a backlog of capacity. It was a budget, divided by demand.

But — and here was the part nobody had mentioned in twenty months — if a patient is referred under Right to Choose, the funding follows the patient through a different, healthier arrangement. Same NHS. Same assessment. Same clinical standards. Radically different queue.

Let me say the quiet part loudly: the appointments existed. What I'd been waiting twenty months for wasn't a clinician's diary to open up. It was a particular pot of money to reach my name.

What Right to Choose actually is

Right to Choose is part of the NHS patient choice framework in England. In plain English: when your GP refers you to a specialist for elective (non-emergency) care, you have a legal right to choose the provider — and that includes independent providers, as long as they hold a contract with the NHS for that service.

Key facts, because precision matters here:

• It's England only. Scotland, Wales and Northern Ireland have different systems (and if you're there, it's worth researching your local equivalents — they differ meaningfully).
• It's still the NHS. You don't pay. This is not "going private". The provider is paid by the NHS under an NHS contract; the only thing that changes is where the referral goes.
• It applies at the point of GP referral. The right kicks in when your GP refers you — which is why the request goes to your GP, not to the clinic.
• **It's a choice of *where*, not a guarantee of *what*.** You're choosing the provider, not purchasing a diagnosis. A proper assessment can end in any conclusion, which is exactly as it should be.
• Several well-known providers run NHS Right to Choose pathways for ADHD and autism assessments, with published waiting-time estimates that are often months — not years. Searching "right to choose ADHD providers" or "right to choose autism assessment" will surface the current options, and charities like ADHD UK maintain helpful, regularly updated lists.

What I did next

I rang my GP surgery and asked them to re-refer me under Right to Choose to a named provider I'd found — one holding an NHS contract for ADHD assessments, accepting RTC referrals, with their referral process documented on their website specifically so GPs could use it.

Two things about that conversation that I'd pass on:

First, I brought the details with me. Provider name, their referral email, a link to their GP information page. The easier you make the admin, the faster the admin happens. A GP being asked "please send this specific form to this specific address under this specific framework" can act immediately. A GP being asked "can I have that Right to Choose thing?" has homework first.

Second, my GP kept the original referral open as a backstop — their sensible suggestion, in case the new route fell through. I'd recommend asking for the same. Belt and braces costs nothing.

The fresh referral went in. I had an assessment date within weeks. Ten weeks — about two and a half months — after the re-referral, I had my diagnosis. After twenty months of nothing, the whole thing was done inside a season.

The punchline the system wrote itself

Here's my favourite part, in the bleakly funny way these things go. Fourteen months *after* my diagnosis — that's thirty-four months after the original referral — the original pathway finally surfaced and offered me an assessment appointment.

I politely told them I'd been diagnosed over a year earlier, on a referral made eighteen months after theirs. Somewhere in a filing system, the queue I escaped is presumably still inching forward.

If I'd done nothing — if I hadn't made one phone call and asked one question — I'd have waited the better part of three years for something Right to Choose delivered in ten weeks.

To be clear: your GP isn't the villain

I want to be fair here, because it would be easy to read this as "my GP failed me", and that's not the story.

GPs are generalists drowning in everything. The mechanics of national commissioning arrangements, which providers hold which contracts, which funding stream a referral draws from, and the existence of a patient-choice framework that most patients never invoke — that's deep administrative weeds, and it changes regularly. My GP didn't withhold Right to Choose from me; they almost certainly didn't have it filed at the front of their mind, because no one had been asking.

That's precisely why the request works best when *you* bring it, fully formed: the framework named, the provider chosen, the referral details attached. You're not challenging your GP — you're doing the logistics homework so they can do the medicine. Mine couldn't have been more helpful once I'd brought them the route.

The system has a side door. It's not hidden out of malice; it's just not signposted. Consider this article the signpost.

The exact steps

1. Confirm you're in England and that this is a GP referral for an ADHD or autism assessment (Right to Choose covers elective referrals generally — but these are the queues where it changes lives). 2. Choose your provider. Search current Right to Choose providers for your assessment type; check they hold an NHS contract and are accepting RTC referrals; save their GP referral instructions. Compare published waiting estimates — they change, so check at the time. 3. Contact your GP — appointment, online consultation form, or a letter via reception. Name the framework, name the provider, attach the details. 4. Already on a waiting list? Ask for the new referral anyway, and ask for the original to be kept open as a backstop. Switching lists is normal and allowed. 5. Confirm it was sent, then confirm the provider received it. One polite chase prevents most paperwork limbo. 6. Do the questionnaires promptly when the provider sends them — that's usually the next gate, and it's one you control.

The email template

Our free Right to Choose Guide (in the starter kit) includes a copy-and-paste email to your GP — the framework named correctly, the provider slot ready to fill in, the already-on-a-list clause included — plus a pre-appointment checklist and the honest fine print. Pop your email in, it arrives instantly, and the wording does the awkward explaining for you.

Things I'd want a friend to know

• Waiting times move. The provider with a 12-week estimate today may say six months next year, and new providers join. Check current numbers when you choose; don't rely on screenshots from a forum post (or, honestly, on this article's specifics — the framework is the durable part).
• Think one step past the assessment. Especially for ADHD: if treatment might follow, ask how the provider handles it, and whether they arrange shared care back to your GP. Shared-care arrangements vary by surgery, and it's better to ask the awkward question early.
• An assessment is an assessment. Some end in a diagnosis, some don't, some end in a different one than expected. The point of cutting the wait isn't securing an outcome — it's getting the question answered while it's still useful to your life.
• If the waiting is heavy, support doesn't have to wait. A diagnosis explains a brain; it doesn't issue the tools. Everything in our Knowledge Hub — the executive dysfunction guide, the sensory toolkit, the masking guide — works the same whether your paperwork has come through or not. So does the two-minute support style quiz, which maps what you're dealing with and what tends to help, no letterhead required.

What the waiting actually costs (and why this matters more than queue maths)

It would be easy to file this under administrative grumbling — queues are queues, everyone waits for everything. But an assessment wait isn't like waiting for a knee scan, where the knee at least knows what it is.

While you wait, you are still failing deadlines without knowing why. Still being told you'd do brilliantly "if you just applied yourself". Still burning out in jobs that quietly require a brain you don't have, masking in rooms that exhaust you, and wondering — in the 2am way — whether the problem is circumstance or character. An assessment doesn't fix any of that on its own. But it reframes all of it, and reframing is where everything else starts: the right tools, the workplace adjustments, the self-forgiveness, sometimes treatment.

Twenty months is a long time to keep paying full price for a question with a discounted answer sitting in a different funding column. That's the real cost of not knowing about Right to Choose — not the wait itself, but everything the wait quietly taxes.

Two practical notes that belong here. First, you don't need the diagnosis to ask for help. Workplaces can make adjustments based on difficulties, not paperwork — our ADHD at work guide covers how to ask without disclosing more than you want to. Universities have similar routes. Don't put your whole life in the waiting room with you. Second, prepare while you wait. Keep a running note of concrete examples — school reports, job patterns, the daily stuff. Assessments lean heavily on real-life evidence, and the person who arrives with specifics has a smoother, fairer hearing than the person trying to retrieve their entire childhood from memory in a ninety-minute appointment.

Twenty months of my wait wasn't medicine. It was a funding pot with my name in the wrong one. One question moved my name — and the question is free.

*This article describes my personal experience and the system as I encountered it — it's practical information, not medical or legal advice. Pathways, providers and waiting times change; check current NHS guidance and provider details when you act. And whatever route you take: good luck. The answer is worth having.*