UK Capital Gains Tax Calculator
The gain, the allowance and your band — and the tax a sale really costs.
Tax Year 2026-27 Individuals and trustees · UK rates and allowances · Rules used
How the tax is worked out
| Step | Amount |
|---|
Rules used · Tax Year 2026-27
- Tax-free allowance (annual exempt amount): £3,000; trusts £1,500 (£3,000 with a vulnerable beneficiary).
- Individuals: 18% on gains that fit in the unused basic rate band (£37,700 of taxable income, extended by gross Gift Aid and relief-at-source pension contributions), 24% above it. Residential property is taxed at the same rates.
- Trustees and personal representatives: 24%.
- Business Asset Disposal Relief and Investors’ Relief: 18%, up to £1 million of qualifying gains each over a lifetime. These gains use the basic rate band before other gains.
- The allowance and losses go against the gains taxed at the highest rate first. Losses of the same year are set off in full; earlier losses only down to the allowance.
- Scottish and Welsh taxpayers use the UK basic rate band for Capital Gains Tax.
Official sources
- GOV.UK: Capital Gains Tax rates
- GOV.UK: Capital Gains Tax allowances
- GOV.UK: Capital Gains Tax losses
- GOV.UK: Business Asset Disposal Relief
- HMRC helpsheet HS308: Investors’ Relief
- HMRC Capital Gains manual CG21204: available basic rate band
- GOV.UK: trusts and Capital Gains Tax
- GOV.UK: reporting and paying Capital Gains Tax
- GOV.UK: work out if you need to pay Capital Gains Tax
Tax rules and rates change. This calculator follows the rules described on this page and may not cover every situation. Check the official source or a qualified tax professional before filing or invoicing.
About the UK Capital Gains Tax Calculator
Capital Gains Tax is charged on the profit when you sell or give away an asset that has gone up in value — shares outside an ISA, crypto, a second home or buy-to-let, business assets. This calculator works out each gain (what you sold it for, less what you paid and the costs of buying, selling and improving it), sets off this year’s losses and earlier losses, takes off the £3,000 tax-free allowance and taxes the rest at 18% within your unused basic rate band and 24% above it.
It also handles Business Asset Disposal Relief and Investors’ Relief (18%, using the basic rate band first), trustees (24% with a £1,500 allowance), and the way Gift Aid and pension contributions widen the basic rate band — and it reminds you when a UK home sale must be reported within 60 days.
How to use it
- Choose whether you sell as an individual or as the trustees of a trust.
- Individuals: enter your income for the tax year before the Personal Allowance, and any gross Gift Aid or relief-at-source pension contributions.
- Add each disposal: its type, what you sold it for, what you paid and your allowable costs. Losses are entered the same way and come out negative.
- Open “Losses from earlier years and lifetime relief used” for losses brought forward or relief claimed in earlier years.
- Read the tax, the taxable gains and the split between rates; copy the summary or download the CSV for your records.
Examples
£12,600 − £3,000 allowance = £9,600 · £20,000 + £9,600 is within the £37,700 basic rate band
£9,600 × 18% = £1,728
£49,600 taxable · £17,700 of basic rate band left
£17,700 × 18% + £31,900 × 24% = £10,842
Taxable income £20,000 · BADR gain £20,000 · share gain £10,000
Allowance against the shares → £20,000 × 18% + £7,000 × 24% = £5,280
The BADR gain fills the £17,700 of basic rate band left, so the share gain is all at 24%.
£10,000 − £1,500 trust allowance
£8,500 × 24% = £2,040
Rates and allowance
- Tax-free allowance (annual exempt amount): £3,000 a year; £1,500 for most trusts and £3,000 for trusts with a vulnerable beneficiary.
- Individuals: 18% on taxable gains that fit in the unused part of the basic rate band (£37,700 of taxable income), 24% on the rest — the same for residential property.
- Trustees and personal representatives: 24%.
- Business Asset Disposal Relief and Investors’ Relief: 18% on qualifying gains, up to a lifetime limit of £1 million for each relief.
GOV.UK: Capital Gains Tax rates · allowances · Business Asset Disposal Relief.
How the basic rate band is used
Add your taxable gains (after the allowance) on top of your taxable income: the part that still fits in the basic rate band is taxed at 18%. Gains with Business Asset Disposal Relief or Investors’ Relief take up the band first. Gross Gift Aid donations and relief-at-source pension contributions extend the band, so more gains fit. Scottish and Welsh taxpayers use the UK band for Capital Gains Tax, not their own Income Tax bands (HMRC CG21204).
Losses
Losses on chargeable assets in the same tax year are deducted from that year’s gains in full. Losses from earlier years are used only to bring the remaining gains down to the tax-free allowance, and what is left carries forward. A loss must be claimed within 4 years of the end of the tax year you made it; you cannot use a loss on a sale or gift to a connected person (such as family) except against gains from that same person. GOV.UK: losses.
Reporting and paying
There is no Capital Gains Tax bill: you work it out and report it. If you sell a UK residential property and have tax to pay, report and pay within 60 days of completion using a Capital Gains Tax on UK property account. Other gains go on your Self Assessment return for the tax year, or through HMRC’s real-time Capital Gains Tax service if you are eligible. If you are registered for Self Assessment, report gains when the total you sold for was more than £50,000, even with no tax to pay. GOV.UK: reporting and paying.
Other countries
Gains taxed in another country follow that country’s rules: the US Capital Gains Tax Calculator works out US federal tax on a sale, and the Capital Gains Tax Calculator (India) the Indian rules.
Limitations
- Your main home is usually exempt through Private Residence Relief; the calculator does not work out partial relief for a home that was let, used for business or very large.
- Shares bought on several dates use HMRC’s share-matching rules (same day, 30 days, the Section 104 pool) to find the cost; enter the cost those rules give.
- Other reliefs (gift hold-over, rollover, EIS deferral), non-residents’ rules and the reliefs for personal representatives are not included.
- Income in the income box is all taxable income; savings and dividend allowances are not worked out separately.
Privacy
Everything happens in your browser. What you enter or open here is not uploaded or stored by MySmartCoPilot.
Frequently asked questions
How much Capital Gains Tax will I pay on shares?
Take what you sold them for, less what you paid and the dealing costs. Add up all gains for the tax year, deduct losses and the £3,000 allowance, then pay 18% on the part that fits in your unused basic rate band and 24% on the rest. Shares inside an ISA are tax-free.
What is the tax-free allowance for Capital Gains Tax?
£3,000 a year for individuals, £1,500 for most trusts. It cannot be carried forward if you do not use it.
Do I pay Capital Gains Tax when I sell my home?
Usually not: Private Residence Relief covers your main home. You may pay on part of the gain if you let it out, used it for business or it is very large; a second home or buy-to-let is taxable.
Is the rate different for property?
No: residential property is taxed at the same 18% and 24% rates as other assets. The difference is timing: UK residential property sales with tax to pay must be reported and paid within 60 days of completion.
Can I reduce my Capital Gains Tax?
Use each year’s allowance (spouses and civil partners each have one, and transfers between them are usually tax-free), claim losses, deduct all allowable costs, and remember that Gift Aid and pension contributions widen the basic rate band. For bigger decisions, get advice from a tax adviser.
I live in Scotland. Do Scottish tax bands apply?
No. Capital Gains Tax uses the UK basic rate band for everyone, so a Scottish taxpayer’s gains are taxed by the same bands as in the rest of the UK.