Severe mental impairment and council tax
Someone with a severe mental impairment, such as advanced dementia, isn't counted for council tax. If they live alone, or only with other people who aren't counted, there's nothing to pay.
Checked against official sources on 27 October 2026. Independent guide; your council decides your bill.
Who qualifies
- a registered medical practitioner, usually a GP, certifies a severe mental impairment, and
- the person is entitled to a qualifying benefit, such as Attendance Allowance, Personal Independence Payment or the Disability Living Allowance care component (your council can give the full list).
What it means for the bill
- Living alone, or only with other disregarded people: 100% off. For example, a person with dementia living alone pays nothing.
- Living with one other adult who is counted: 25% off, as with the single person discount.
- Living with two or more other counted adults: no change to the bill.
Wales: significant cognitive impairment
Since 1 April 2026 Wales uses the term "significant cognitive impairment", defined as a severe and permanent mental condition or neurological change that affects how the brain functions. The effect on the bill is the same.
England: changes planned
In April 2026 the government said it will rename and redefine the severe mental impairment disregard in England when parliamentary time allows, and introduce an optional standard application form.
Questions
Is there a council tax discount for dementia?
Yes, if a doctor confirms a severe mental impairment, which can include dementia, and the person gets a qualifying benefit. They aren't counted for council tax: someone living alone pays nothing, and a household where they live with one other adult gets 25% off.
What does "severely mentally impaired" mean?
A severe impairment of intelligence and social functioning that appears to be permanent, confirmed by a registered medical practitioner. In Wales the term was replaced on 1 April 2026 by "significant cognitive impairment".
Can the discount be backdated?
Ask your council when you apply. If the conditions were met before you applied, for example from the date of diagnosis and benefit award, it may be able to apply the discount from then.