Capital gains tax calculator
Capital gains tax with the annual exempt amount and the gain stacked on income to decide the rate.
Capital gains tax
Estimate$4,784.00
3,000 exempt, then 18% and 24%
- Gain after tax
- $20,216
- Taxed at 18%
- $8,270.00
- Taxed at 24%
- $13,730
| Gain | $25,000 |
|---|---|
| Annual exempt amount | -$3,000.00 |
| Basic-rate headroom after income | $8,270.00 |
| At 18% | -$1,489.00 |
| At 24% | -$3,295.00 |
| Gain after tax | $20,216 |
- The gain sits on top of your income, so £8,270 of basic-rate band is left before the higher rate applies.
- The annual exempt amount fell from £12,300 in 2022-23 to £3,000, so far more disposals are now reportable.
On a £25,000 gain with £42,000 of income, £3,000 is exempt and only £8,270 of basic-rate band remains, so most of the gain is taxed at the higher rate.
How this is calculated
How this is calculated
Gains are usually stacked on income
Income fills the lower band first, so the rate on a gain depends on both. With £42,000 of income against a £50,270 UK band edge, only £8,270 of gain gets the 18% rate.
headroom = band edge − incomeTax-free allowances have shrunk
The UK annual exempt amount fell from £12,300 in 2022-23 to £3,000, so disposals that were previously invisible now need reporting and often produce tax.
Loss ordering changes the result
Same-year losses generally reduce the gain before the exemption is applied, while carried-forward losses are used after it. On a £25,000 gain that ordering decides whether the £3,000 exemption is spent or preserved for later years.
Worked example: £25,000 gain with £42,000 of income
| Gain | £25,000 |
|---|---|
| Income | £42,000 |
| Exempt | £3,000 |
|---|---|
| Split | Across two rates |
Capital gains rules differ by country. Pick a country above for the rates and exemptions that apply to you.
What this assumes
- A resident individual, not a company or trust.
- Assets held outside a tax wrapper.
- No losses brought forward.
- No special business reliefs claimed.
Where this commonly goes wrong
- Property gains often have a short separate reporting and payment deadline distinct from the annual return.
- Selling and rebuying the same asset within a set window is commonly disregarded, so the intended gain is not crystallised.
- Transfers between spouses are frequently exempt and can double the available annual exemption.
Questions
How is capital gains tax calculated?
The gain less any annual exemption is stacked on top of your income. In the UK that means £3,000 is exempt and the remainder is taxed at 18% or 24% depending on how much basic-rate band your income leaves.
Why does my income affect the rate on a gain?
Because the gain is treated as the top slice of your income. With £42,000 of income against a £50,270 band edge, only £8,270 of gain gets the lower rate and everything above is charged at the higher one.
How can the bill be reduced?
Spreading disposals across tax years uses more than one annual exemption, transfers between spouses can double it, and gains inside a tax wrapper are usually exempt entirely.
Related tools
Sources
General estimate based on published HMRC rates for the current period. Not tax advice. Confirm your position with HMRC or a qualified adviser.
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