Private vs NHS assessments: what parents need to know
NHS waiting lists for autism and ADHD assessments can stretch to years. Here's an honest comparison of private and NHS routes — costs, acceptance, and what to consider.
Why parents consider going private
The main reason is speed. NHS waiting times for autism assessments average 18 months to 3 years in many parts of the UK. ADHD assessment waits are often 12 to 24 months. For a parent watching their child struggle daily — at school, socially, emotionally — these waits feel impossible. And they are: a child's needs don't pause while they wait for a diagnosis.
A private assessment can typically be arranged within 4 to 8 weeks. For families who can afford it, this faster route means earlier access to understanding, strategies, and the formal evidence needed for school support and EHCP applications.
What private assessments cost
Private autism assessments (multi-disciplinary, using ADOS-2 and ADI-R) typically cost between £1,500 and £3,000. ADHD assessments range from £800 to £2,000. Dyslexia assessments by a specialist educational psychologist are usually £400 to £800. Educational psychology assessments (cognitive and learning profile) run £600 to £1,200.
These are significant sums, and it's worth being realistic about whether you can afford it. Some assessment services offer payment plans. Some families use savings, borrow from family, or fundraise. There's no shame in any of these — you're investing in understanding your child.
Are private assessments accepted?
Yes — private assessments by qualified professionals are accepted by schools, Local Authorities, and the NHS. A private autism diagnosis from a team that follows NICE guidelines (using recognised assessment tools like ADOS-2) carries the same weight as an NHS diagnosis.
However, some GPs or NHS services may want to "verify" a private diagnosis before prescribing medication (particularly for ADHD). This is becoming less common, but it's worth asking the private assessor about their experience with local NHS services accepting their reports.
For EHCP applications, private professional reports are treated as evidence alongside NHS reports. A strong private educational psychology report can be particularly valuable.
What to look for in a private assessor
Check their professional registration: clinical psychologists should be HCPC-registered, educational psychologists should be HCPC-registered, paediatricians should be GMC-registered. For autism assessments, ask whether they use ADOS-2 and involve a multi-disciplinary team (the gold standard).
Ask about their report turnaround time (2 to 4 weeks is typical), whether the report includes specific recommendations (not just a diagnosis), and whether they offer a feedback session to discuss findings with you. A good assessor will want to understand your child in context, not just run through a checklist.
The NHS route: what to know
The NHS route is free, and for many families it's the only affordable option. The quality of NHS assessments is generally high — the issue is waiting times, not quality. Your GP can refer to the local child development service (for autism) or CAMHS (for ADHD and mental health).
While waiting, ask the school to put SEN support in place based on your child's presenting needs. You don't need a diagnosis for the school to provide extra help. Document everything — keep notes of what's been tried and what's working or not working. This evidence will be valuable whenever the assessment happens.
Some areas offer a "Right to Choose" pathway for ADHD, where you can request the NHS funds your assessment with an approved private provider. Ask your GP about this.
Can you do both?
Yes. Some families get a private assessment for speed, then remain on the NHS waiting list. This can be useful if you need NHS follow-up services (like ADHD medication titration) or want a "belt and braces" approach. Inform both services that you're pursuing parallel routes — they should be aware.
Another approach: get a private educational psychology assessment (for EHCP evidence) while waiting for an NHS diagnostic assessment (for the formal diagnosis). The two serve different purposes and complement each other well.