Dyscalculia is a lifelong difficulty with numbers and quantities. In the UK it is not an NHS diagnosis but an educational specific learning difficulty, assessed by an educational psychologist or APC-holding assessor.
What dyscalculia actually is
A specific learning difficulty, or SpLD, is a difference in how the brain processes one particular type of information, sitting alongside otherwise typical ability. With dyscalculia, the part that is affected is number sense: naming, ordering and comparing quantities, estimating, and grasping place value. A child with dyscalculia may struggle to tell which of two numbers is bigger, to read a clock, or to hold figures in their head for mental arithmetic, while doing perfectly well in subjects that do not lean on number.
The current UK standard, the SASC 2025 definition, frames dyscalculia as the number-sense subtype within a broader specific learning difficulty in mathematics. SASC is the SpLD Assessment Standards Committee, the body that sets the rules assessors follow. National Numeracy estimates dyscalculia affects around 3% of people, which is roughly one child in every classroom.
Why the NHS won't diagnose it
This is the part most parents are surprised by, and it is where most of the confusion comes from. Dyscalculia is not a medical condition that a GP or the NHS diagnoses, the way autism and ADHD are. There is no NHS dyscalculia clinic to be referred to, and the NHS does not have a dyscalculia page in its conditions list. Asking your GP for a referral will not produce a dyscalculia diagnosis.
Instead, dyscalculia is recognised in education. The SEND Code of Practice 2015 lists it (at paragraph 6.31) as a specific learning difficulty under the “cognition and learning” area of need. So the route to having it identified runs through school and educational assessment, not through a doctor.
Who can diagnose it, and how
A formal identification of dyscalculia comes from a full diagnostic assessment, and only two kinds of professional are qualified to carry one out:
- An educational psychologist registered with the Health and Care Professions Council (the HCPC, which licenses psychologists). An educational psychologist, or EP, looks at how a child learns rather than treating an illness.
- A specialist assessor who holds a current Assessment Practising Certificate (an APC) for maths. The APC is the licence that makes an assessment count, and it must follow the current SASC Maths Difficulties and Dyscalculia Guidance, updated in March 2025.
A proper assessment is not a single test. As the British Dyslexia Association explains, it uses several measures together: general ability, underlying skills such as working memory and processing speed, and maths attainment. That is what separates a real diagnosis from an online quiz or a quick school screening, which can flag a concern but cannot diagnose. Dyscalculia can be identified at any age.
Why this matters for what you do next
Two practical points follow. First, a diagnosis is not the gate to support: schools must help any pupil with special educational needs through SEN Support, based on what the child finds hard, with or without a label. Second, if you do want a formal assessment, you usually arrange it yourself with a private assessor, because there is rarely a free route. Choose someone listed by the BDA, SASC or Patoss, and check they hold a current APC.
Where the law comes from
Related
This page is general information, not clinical or legal advice.