Capital Gains Tax on what you sold
Your income decides the rate — the same gain costs different people different amounts.
Salary, dividends, rent — before tax. This decides your CGT rate
Sale price minus what you paid and minus buying/selling costs
Losses on assets you sold in this same tax year. These must be used in full, even if that wastes your exempt amount
Unused losses from earlier years. These are only used down to your exempt amount — the rest stays available
Capital Gains Tax to pay
£3,163.80
15.8% of your total gain
Annual exempt amount
£3,000.00
Deducted before the rate is worked out
Taxable gain
£17,000
Gain you keep
£16,836
Your gain is taxed at two different rates
| Total gain | £20,000.00 |
|---|---|
| Annual exempt amount | −£3,000.00 |
| Taxable gain | £17,000.00 |
| 18.0% On £15,270 | £2,748.60 |
| 24.0% On £1,730 | £415.20 |
| Capital Gains Tax | £3,163.80 |
What this does not cover
Figures for the 2026/27 UK tax year. Rates last checked against HMRC on 2026-08-28. See every source.
How to work out your Capital Gains Tax
Capital Gains Tax is not a flat rate. Gains are added on top of your taxable income, so the part that still fits inside the basic rate band is taxed at 18% and everything above it at 24%. Two people selling identical assets can pay very different bills. This calculator asks for your income first for that reason, then splits the gain across both rates. It also flags unused annual exempt amount, which is worth knowing before 5 April: the allowance cannot be carried forward, so anything you do not use is simply lost. From April 2026 residential property and other assets share the same pair of rates — older articles quoting 28% are out of date.
- 1Enter your other income for the year — this is what decides your rate, so it is not optional.
- 2Enter the gain: what you sold it for, less what you paid, less buying and selling costs.
- 3Add any capital losses, from this year or carried forward from earlier years.
- 4Read the split between the two rates, and check whether you are leaving allowance unused.
FAQ
Why is my rate 24% when I thought basic rate taxpayers paid 18%?
The gain itself pushes you up. Your taxable income uses part of the basic rate band, and the gain sits on top of it. Only the room left inside the band is taxed at 18% — everything above it is taxed at 24%, even if your salary alone would have kept you a basic rate taxpayer.
Can I carry unused annual exempt amount into next year?
No. It is use-it-or-lose-it each tax year. If you hold other assets standing at a gain and you have allowance going spare, selling some before 5 April uses it up. Selling a large holding across two tax years instead of one can also use two years of allowance and keep more of the gain in the lower band.
Do I pay Capital Gains Tax on selling my home?
Normally no — Private Residence Relief covers a home you have lived in throughout your ownership. It gets more complicated if you let it out, used part of it exclusively for business, or owned it before or after living there, and this calculator does not model any of those cases.
When is it due?
For most assets, through Self Assessment by the following 31 January. UK residential property is different and much tighter: the gain has to be reported and the tax paid within 60 days of completion, separately from your tax return.