Council tax assumes two adults in every home, and knocks a quarter off when there is only one. The question that arrives with a change in the household is whether the newcomer counts. Some adults do not, by law, and the list is longer than the leaflet suggests: a student, a carer, a person with dementia, someone who has gone into a care home.
The discount itself
GOV.UK says you get 25% off your bill if you pay council tax and either you live on your own or everyone else in your home is disregarded, and 50% off if everyone living in the household is disregarded (GOV.UK, How Council Tax works: who has to pay, checked 1 November 2026).
It is not means-tested. It is claimed from the council, and once granted it runs until the household changes.
Disregarded means not counted as an adult for this purpose, and our discount checker applies the rules to the adults you list. GOV.UK’s list includes people under 18, those on certain apprentice schemes, 18 and 19 year olds in full-time education, full-time students, student nurses, people who are severely mentally impaired, live-in carers for someone who is not their partner, spouse or child under 18, and diplomats.
When an adult child comes home
A son or daughter over 18 who is in work, between jobs or on Universal Credit counts as an adult, and the discount ends from the day they move in. GOV.UK says you must tell the council about a change that affects your bill.
A discount claimed while two adults live in the home is recovered when the council finds out.
Two exceptions matter at this age. A full-time student, including one home for the summer whose course continues, is disregarded. So is an 18 or 19 year old still in full-time education. If you get Council Tax Reduction as well, an adult child brings a non-dependant deduction on top; our council tax hub has the 2026/27 figures, and the Housing Benefit equivalent is larger.
When a carer moves in
The Act disregards a person who is engaged in providing care or support to another person, on conditions set by regulations (Local Government Finance Act 1992, Schedule 1, paragraph 9, checked 1 November 2026). The regulations set four, starting with 35 hours a week of care on average.
The carer must live in the same dwelling as the person cared for, and must not be a disqualified relative.
The person cared for must be entitled to Attendance Allowance, the highest or middle rate of the care component of DLA, the daily living component of PIP at either rate, or Armed Forces Independence Payment. A disqualified relative is the spouse or civil partner of the person cared for, someone living with them as if married, or, where the person cared for is a child under 18, that child’s parent (Council Tax (Additional Provisions for Discount Disregards) Regulations 1992, checked 1 November 2026).
So a daughter who moves in to care for her mother, 35 hours a week, with an Attendance Allowance award in place, is not counted, and her mother keeps the single person discount. A husband caring for his wife is not disregarded on this ground, though she may be on another.
When someone has dementia
A person who meets the severe mental impairment test is disregarded whoever they live with. The test is a doctor’s certificate of a severe impairment of intelligence and social functioning that appears permanent, plus entitlement to a qualifying benefit, such as Attendance Allowance. A spouse living with them gets 25% off; a person living alone with the impairment pays nothing.
Our severe mental impairment page covers the claim, the benefits that qualify, and backdating.
When someone goes into hospital or a care home
The Act disregards a person who has their sole or main residence in a care home, independent hospital or hostel and is receiving care or treatment there. A wife whose husband has moved into a care home permanently is living alone for council tax, and gets the 25%.
That is paragraph 7 of Schedule 1 (Local Government Finance Act 1992, Schedule 1, paragraph 7, checked 1 November 2026).
If both go, or the remaining partner moves out too, the empty home can be exempt under Class E, provided the person in care was an owner or tenant; the Order sets no time limit while it stays unoccupied (Council Tax (Exempt Dwellings) Order 1992, article 3, checked 1 November 2026). Class I does the same for a home left to receive personal care elsewhere, such as at a relative’s. Our paying for care hub covers what a care home move does to the rest of the household’s money.
Lodgers, and what to tell the council
A lodger counts as an adult unless they are disregarded on one of the grounds above, so the discount ends when they move in. Rent from a lodger is income the council will ask about for Council Tax Reduction and Housing Benefit, so a lodger changes the means test as well as the discount.
Our Housing Benefit hub covers the reporting duty there.
Tell the council in writing when anyone moves in or out, and say on what ground you think the newcomer is disregarded. A student certificate, a carer’s statement of hours with the Attendance Allowance award letter, or a doctor’s certificate for severe mental impairment is what the council will ask for. A discount ends from the date of the change, and a wrongly continued one is billed back to that date.
The disabled band reduction
Separate from all of the above, GOV.UK says the Disabled Band Reduction Scheme moves a home down one band where a disabled person needs an extra room, an extra bathroom or kitchen, or space for a wheelchair indoors, and gives a 17% reduction on a Band A home (GOV.UK, How Council Tax works: discounts for disabled people, checked 1 November 2026).
It turns on the adaptations, not on who lives there, and it sits alongside the discounts rather than replacing them.