In short
You don't pay tax on a competition prize in the UK. Not income tax, not capital gains, not anything. Win a £100,000 car or take £75,000 in cash and it's all yours — there's nothing to declare and no form to fill in.
Where tax can appear is afterwards. Put the cash in a savings account and the interest is taxable like any other. Claim Universal Credit and a big lump sum can push you over the savings limit. And if you're unlucky enough to die with the car still in the garage, it's part of your estate for inheritance tax.
The one genuine trap: if your employer runs the competition, HMRC may treat the prize as pay. Everything else is worry-free.
Why competition prizes aren't taxed
UK income tax applies to income — wages, profits from a trade, rent, interest, dividends and so on. A prize you win by buying a ticket and answering a skill question isn't any of those. HMRC treats it the same way it treats a lottery win, a Premium Bond prize or a bet that comes in: it's a windfall, not earnings.
That holds whether the prize is a car, a house, a holiday or cash. It also holds for the cash alternative — the money you take instead of the vehicle is still a prize, not income.
There's no need to report it on a self-assessment return, and the operator won't deduct anything before paying you. If you're an employee on PAYE and have never filed a tax return, winning a car doesn't change that.
What about capital gains tax?
Also no. Capital gains tax applies when you sell an asset for more than you paid for it. Two things protect a competition winner here.
First, private cars are exempt from CGT altogether. HMRC treats them as "wasting assets" — things expected to lose value over time — so selling a car you won, even a supercar that's held its value, doesn't create a taxable gain.
Second, if you take cash, there's no asset to sell. The lump sum is simply yours.
The one edge case is a non-car prize that appreciates — a watch, say, or a piece of art — sold later for more than its value when you won it. That could in theory trigger CGT on the gain above your annual allowance. It's unusual, but worth knowing if you enter competitions for high-value items other than vehicles.
Where tax does come in
Interest on the cash
If you take the cash alternative and put it in a savings account, the interest it earns is taxable in the normal way. You get a Personal Savings Allowance — currently £1,000 for basic-rate taxpayers and £500 for higher-rate — and anything above that is taxed at your marginal rate. Sheltering the money in an ISA avoids this entirely, up to the annual limit.
The prize itself is never taxed. Only what it earns afterwards.
Means-tested benefits
This one matters more than tax for a lot of winners. Universal Credit, Housing Benefit and similar means-tested benefits have a savings threshold. If your capital goes over £16,000, you lose eligibility; between £6,000 and £16,000, your payments are reduced.
A cash alternative counts as capital. So does a car you could sell, in some circumstances — though a single vehicle used for personal transport is usually disregarded. If you claim benefits and win, it's worth getting advice from Citizens Advice before you decide between the car and the cash.
Inheritance tax
A prize becomes part of your estate like any other asset. If you die with a £150,000 car in the garage or the cash still in the bank, it's counted towards the inheritance tax threshold. This is only relevant if your total estate is over the nil-rate band — £325,000 for most people — but a big win can be what tips it over.
Prizes from your employer
If the competition is run by your employer — a staff prize draw, an incentive scheme, "win a car for hitting target" — HMRC is likely to treat the prize as employment income and it may be taxed through payroll or as a benefit in kind. The same can apply to prizes from a company you contract for. This doesn't affect public competitions you enter as a member of the public.
If entering competitions is your trade
There's an old HMRC principle that if something is your trade, the proceeds are taxable. In theory, a professional "comper" who enters competitions systematically for profit could be argued to be trading. In practice this almost never applies to prize draws — the outcome depends on chance, not skill, so it's hard to call it a business — but it's worth mentioning for completeness.
Costs that aren't tax but feel like it
Winning a car isn't quite free once it's on your drive.
Vehicle Excise Duty (road tax). Payable as normal once the V5C is in your name. First-year rates on high-value new cars can be several thousand pounds.
Insurance. Yours to arrange before you drive it. Supercar and performance car premiums vary enormously by age, postcode and driving history — get a quote before you decide between the car and the cash.
The "expensive car supplement". New cars with a list price over £40,000 pay an additional VED charge for the first five years. If the car you win is new, this applies to you.
None of these are taxes on the prize. They're the normal running costs of owning the car, and they're one of the main reasons winners take the cash alternative instead.
What to keep for your records
You don't need to report the win, but it's sensible to keep:
The competition confirmation and winning ticket number.
The operator's written confirmation that you've won, and the prize or cash figure.
The V5C and any handover documents if you take the car.
Bank records showing the cash alternative arriving, if you take the money.
This is mainly for your own protection — if HMRC ever queries an unusual deposit, or a bank asks about the source of funds, a clean paper trail from a named UK company answers the question in seconds.
Frequently asked questions
Do I pay tax if I win a car in a competition? No. Competition prizes aren't income, so there's no income tax to pay and nothing to declare.
Do I pay tax on the cash alternative instead? No. The cash alternative is still a prize. Only interest earned on it afterwards is taxable.
Will HMRC know I've won? There's no reporting requirement on either side. The operator doesn't tell HMRC and you don't need to either.
Does winning a car affect my Universal Credit? It can. A cash alternative counts as savings, and going over £16,000 ends eligibility. A single car used for personal transport is usually disregarded. Get advice before choosing.
Do I pay capital gains tax if I sell the car later? No. Private cars are exempt from CGT regardless of how you acquired them or what you sell them for.
Is a competition prize taxed differently from a lottery win? No. HMRC treats both as tax-free windfalls.
What if I win a competition run by my employer? That's different. Prizes from employers are usually treated as employment income and taxed accordingly.
Do I need to tell my student loan company? No. Student loan repayments are based on income, and a prize isn't income.