If you or someone you care for has a severe mental impairment, there is a good chance they could be entitled to a 100% discount on council tax — meaning they pay nothing. It is one of the most generous council tax benefits available, and yet it is chronically underclaimed: millions of pounds go unclaimed every year, simply because people do not know the discount exists or do not realise they qualify. The good news is that it is free to apply for and the process is straightforward. This guide sets out what the discount is, who qualifies, what evidence you need, and how to make a claim.
What Is the Severe Mental Impairment Discount?
In England, Scotland, and Wales, people who are severely mentally impaired are “disregarded” for council tax purposes. That means they are not counted when the council works out how many adults live at a property. If a disregarded person lives alone — or everyone else in the household is also disregarded — the council tax bill is reduced to £0.
How It Works in Practice
The council tax system normally assumes two adults at a property. If one adult is disregarded because of severe mental impairment, the council treats the property as having only one adult, which gives you the 25% single person discount. But if you live alone, or if everyone else in your household is also a disregarded person (for example, a full-time student or another person with severe mental impairment), the 100% disregard applies and you pay nothing.
Example: A couple live together. One has Alzheimer’s disease and qualifies as severely mentally impaired, and is therefore disregarded. The other adult becomes the only “counted” person, so they get the single person discount — 25% off. If the unaffected adult also moves out (for example, into residential care), the disregarded person lives alone and pays nothing.
Who Qualifies as Severely Mentally Impaired?
A person qualifies if they have a permanent condition that severely impairs their intellectual or social functioning. Councils will typically accept conditions including:
- Dementia (including Alzheimer’s disease)
- Severe learning disabilities (for example, people who need 24-hour care)
- Parkinson’s disease (with cognitive impairment)
- Severe head injury resulting in cognitive impairment
- Severe stroke with lasting cognitive effects
- Advanced multiple sclerosis with cognitive symptoms
- Other conditions causing permanent, severe cognitive impairment
What “Severely Mentally Impaired” Means
The legal definition requires the person to be in a permanent state of mind such that they:
- Cannot care for themselves
- Cannot manage their own affairs
- Have a severe and permanent impairment of intellectual or social functioning
This is not the same as having a mental health condition such as depression or anxiety. The condition must be permanent — or expected to be permanent — and must cause severe impairment.
Evidence Required
To prove severe mental impairment, the council typically requires:
- A GP or consultant medical certificate confirming the condition and that it is permanent and severely impairing
- Proof of entitlement to certain benefits (this helps but is not always required):
- Attendance Allowance
- Personal Independence Payment (PIP) – daily living component
- Disability Living Allowance (DLA) – care component at the middle or higher rate
- Incapacity Benefit (for claims before April 2001)
- Employment and Support Allowance (ESA) – support component
If the person does not receive any of these benefits, the council may still accept a medical certificate on its own — but this varies by authority, and some councils are stricter than others.
Who Can Claim?
The disregard can be claimed by:
- The person with severe mental impairment themselves (if they have the capacity to do so)
- A carer acting on their behalf (with appropriate authority, such as Power of Attorney)
- A family member who lives at the property and is responsible for the council tax bill
- Anyone who is the “liable person” for the council tax at that address
If the person lives alone, the 100% disregard applies and they pay nothing. If they live with others, each disregarded adult reduces the number of “counted” adults. For example:
- Two adults, one disregarded: treated as one adult — 25% discount
- Three adults, one disregarded: treated as two adults — no discount
- Two adults, both disregarded: treated as no adults — 100% discount (pay nothing)
If the person has moved into a care home permanently, the property may qualify for a disregard under the rules for empty properties, so it is worth checking with your local authority.
How to Claim, Step by Step
The process varies a little by council, but the broad steps are the same everywhere.
Step 1: Confirm eligibility. Check that the person has a condition that qualifies as severe mental impairment. If in doubt, ask their GP or consultant.
Step 2: Get medical evidence. Ask the person’s GP or consultant to provide a medical certificate confirming the person’s name and address, the diagnosis (for example, “severe dementia”), that the condition is permanent (or expected to be permanent), and that it severely impairs their intellectual or social functioning. Some councils have their own forms for this, so contact the local authority’s council tax team to ask what they require.
Step 3: Check benefit entitlement. See whether the person receives, or could apply for, Attendance Allowance (if they need help with personal care), PIP Daily Living Component (if they need help with daily activities), or DLA Care Component (for children or pre-2013 claims). If they do not receive any of these, it may still be worth applying — the medical evidence used for the council tax discount can sometimes support a benefits application too.
Step 4: Contact your local authority. Get in touch with your council’s council tax team, whose details you can usually find on your council tax bill or on the local authority’s website (search “[council name] council tax team”). Tell them you want to apply for the severe mental impairment disregard. They will send you an application form if they have one, tell you what evidence they need, and explain their process and timescales.
Step 5: Submit your application. Send the council the completed application form (if required), the GP/consultant medical certificate, proof of any relevant benefits (benefit award letters), and your council tax account number if you have one. Keep copies of everything you send.
Step 6: Wait for a decision. The council will review your application, which typically takes 2–6 weeks. They may accept the application and apply the discount, ask for additional evidence, arrange a medical assessment (rare, but possible), or reject the application (in which case you can appeal).
Step 7: Receive your updated bill. If approved, the council issues a new council tax bill with the discount applied. They will also refund any overpayments — typically back to the date you first notified them, rather than back to the start of the financial year.
How Much Can You Save?
The savings are significant, especially where the person with severe mental impairment lives alone:
| Scenario | Band D Annual Bill | After Discount | Annual Saving |
|---|---|---|---|
| Person with SMI lives alone | £2,000 | £0 | £2,000 |
| Couple, one has SMI | £2,000 | £1,500 | £500 |
| Three adults, one has SMI | £2,000 | £2,000 | £0 |
The biggest saving comes when the person with severe mental impairment lives alone, because the entire bill is covered. And because the discount applies year after year, those savings accumulate: typically £1,000–£2,000 saved per year, £5,000–£10,000 saved over five years, and potentially more as council tax rises each year.
Common Mistakes and How to Avoid Them
Not applying because you think you won’t qualify. Many people assume the discount is only for people in care homes or for people on full disability benefits. It is not. Even if the person does not receive Attendance Allowance or PIP, the council may still accept a medical certificate.
Not getting the medical certificate. Some people apply without medical evidence and are rejected. The GP or consultant letter is the single most important piece of evidence, so get it before you apply.
Not telling the council when circumstances change. If the person’s condition improves — unlikely with conditions like dementia, but possible with others — you must notify the council. If they no longer qualify, the discount will be removed, and failing to notify the council could lead to penalties.
Not claiming the single person discount when only one adult remains. If the person with severe mental impairment moves into care, the remaining adult may be left alone at the property and should claim the single person discount if applicable.
England, Scotland, and Wales
The severe mental impairment disregard applies in all three countries, with only minor differences:
| Factor | England | Scotland | Wales |
|---|---|---|---|
| Applies? | Yes | Yes | Yes |
| Discount | 100% disregard | 100% disregard | 100% disregard |
| Medical evidence | GP or consultant certificate | GP or consultant certificate | GP or consultant certificate |
| Benefits accepted | Attendance Allowance, PIP, DLA | Attendance Allowance, PIP, DLA | Attendance Allowance, PIP, DLA |
Northern Ireland runs a different system. The discount may apply there, but the rules and process are different, so it is best to contact the local council for details.
What If Your Application Is Rejected?
Rejection is not the end of the road. You can:
- Ask for a review — provide additional evidence or ask the council to reconsider
- Appeal to the Valuation Tribunal — a free, independent tribunal. You must appeal within 2 months of the council’s decision
- Get help from Citizens Advice, which can help you prepare your appeal
For a stronger appeal, get a detailed letter from the GP or consultant explaining the severity of the impairment, provide evidence of how the condition affects daily life, include benefit award letters showing the person needs care, and explain how long the condition has been present.
An Underclaimed Benefit
Research consistently shows that the severe mental impairment council tax disregard is one of the most underclaimed benefits in the UK. Many people with dementia, Alzheimer’s, and severe learning disabilities are currently paying council tax they should not be paying. If you know someone who might qualify — a relative, a neighbour, or someone you care for — it is worth raising it with them. A five-minute phone call to the council could save them £1,000 or more a year, and the discount continues to apply year after year once it is in place.