Capital Gains Tax on a £25,000 Gain 2026/27
After the £3,000 annual exempt amount, a basic-rate taxpayer (£35,000 other income) owes £4,364 CGT on a £25,000 gain. A higher-rate taxpayer (£55,000 other income) owes £5,280.
A £25,000 gain gives £22,000 of taxable gain, and the bill lands anywhere from £3,960 to £5,280 depending on income. It is a common size for a long-held share portfolio or cryptoassets bought years ago, and it is big enough that timing a sale across 5 April 2027 is worth more than the second allowance alone.
Which rate does a £25,000 gain pay at different incomes?
| Other income | Band left | At 18% | At 24% | CGT |
|---|---|---|---|---|
| £20,000 | £30,270 | £22,000 | £0 | £3,960 |
| £35,000 | £15,270 | £15,270 | £6,730 | £4,363.80 |
| £45,000 | £5,270 | £5,270 | £16,730 | £4,963.80 |
| £55,000 | £0 | £0 | £22,000 | £5,280 |
On £35,000 of income, £15,270 of the gain is at 18% and £6,730 at 24%, £4,363.80 in total. The 18%-only line is £28,270 of income, which most full-time earners are above. A seller on £45,000 has just £5,270 of band left, so the gain is taxed mostly as if they were a higher-rate taxpayer: £4,963.80, only £316.20 short of the £5,280 paid on £55,000.1
Can you pay less on a £25,000 gain?
| Option | CGT | Saving |
|---|---|---|
| Sell it all in 2026/27 | £5,280 | - |
| Half before 6 April 2027, half after | £4,560 | £720 |
| Half given first to a spouse with no income | £3,990 | £1,290 |
| Half given first to a spouse earning £35,000 | £3,990 | £1,290 |
| £10,000 gross pension contribution | £4,963.80 | £316.20 |
| £20,000 gross pension contribution | £4,363.80 | £916.20 |
Spreading the sale over two tax years
Split evenly across two tax years, the basic-rate seller saves £943.80. Each £12,500 half leaves £9,500 taxable, which fits inside the £15,270 band, so none of the gain reaches 24% on top of the second allowance. A higher-rate seller still saves only £720. If you were going to sell either side of 5 April 2027 anyway, this is the simplest lever on the page.
Giving half to a spouse or civil partner
Half to a spouse with no income saves £1,290. The transferred half is taxed as their gain, worked out from the value when you first owned it,2 so keep the original contract notes or exchange records: both of you will need them to show the cost.
Pensions, ISAs and reliefs
A seller on £35,000 could cover the £6,730 spill by paying the same amount more into a workplace pension by salary sacrifice or net pay, saving £403.80. The law extends the basic rate limit for a personal pension contribution only where some income would otherwise be taxed at the higher rate, so at £35,000 the workplace route is the safe one.3 A higher-rate seller saves £316.20 with £10,000 gross and £916.20 with £20,000.3 Relief is limited to contributions of up to 100% of your earnings for the year.5
Reporting and paying the tax
Report it by the deadline for your route: Self Assessment by 31 January 2028 for a 2026/27 sale, or the real-time service by 31 December 2027 if you are not in Self Assessment.4 HMRC can ask to see your working, so keep the cost, dates and fees of each purchase; for shares bought in several lots, the cost comes from the Section 104 pool.
Your own figures: use the full calculator → for your sale price, costs, losses and income.
CGT on other gain amounts
Frequently asked questions
What is the CGT on a £25,000 gain for a higher-rate taxpayer?
£5,280: the £22,000 left after the £3,000 allowance, all at 24%. That is 21.1% of the whole gain.
Can I cut CGT on £25,000 by selling at the end of March?
Only if you also sell part after 5 April. A single sale on 31 March 2027 is taxed in 2026/27 with that year's allowance; it is splitting between the two years that saves £943.80 to £720.
Was CGT on a £25,000 gain the same in 2025/26?
For the same income, yes. The rates were 18% and 24% for the whole of 2025/26 with the same £3,000 allowance, and the income tax bands were frozen at the same levels.
Figures from our calculator engine, 7 November 2026. Guidance only, not advice.
Sources & references
The rates, allowances and rules in this guide are drawn from the official HMRC and GOV.UK sources below, checked for the 2026/27 tax year. Each link opens the relevant government page in a new tab.
- Capital Gains Tax: rates www.gov.uk/capital-gains-tax/rates
- Capital Gains Tax: gifts to your spouse or charity www.gov.uk/capital-gains-tax/gifts
- Finance Act 2004, section 192: relief at source (basic rate limit increased by the contribution) www.legislation.gov.uk/ukpga/2004/12/section/192
- Report and pay CGT: if you have other capital gains to report www.gov.uk/report-and-pay-your-capital-gains-tax/if-you-have-other-capital-gains-to-report
- Tax on your private pension contributions: tax relief www.gov.uk/tax-on-your-private-pension/pension-tax-relief