UK Capital Gains Tax Calculator (2026/27)

Work out UK Capital Gains Tax for 2026/27 or 2025/26: gain, £3,000 allowance, losses and the 18% / 24% rates based on your income, plus BADR.

Tax year of the sale

What did you sell?

Disposal proceeds / required market value (£)

Allowable acquisition cost / tax basis (£)

Allowable costs (£)Buying and selling fees, stamp duty paid when you bought, and improvement costs

Income before the Personal Allowance (£)Salary, pension, rental profit, interest and dividends, before the Personal Allowance

Gross personal pension contributions and Gift Aid (£)Relief-at-source contributions extend your basic rate band

Other gains in the same tax year (£)

Losses in the same tax year (£)Other allowable losses this year; do not enter a loss on this disposal again.

Unused losses from earlier years (£)

Remaining lifetime relief limit (£)For BADR / Investors’ Relief only: remaining limit for the selected relief after all earlier claims. Mixed relief types or gains above this limit need a separate calculation.

Estimate UK Capital Gains Tax for a UK-resident individual in 2025/26 or 2026/27. Enter an already established allowable tax basis and disposal proceeds, or market value where required. The tool calculates a gain or loss, applies allowable losses and the £3,000 annual exemption, and uses your income to split ordinary taxable gains between 18% and 24%.

How to use this tool

Select the tax year and ordinary gains or one qualifying relief category.
Enter proceeds, allowable acquisition basis and additional disposal costs without duplication.
Enter income before the Personal Allowance and eligible gross relief-at-source pension contributions or Gift Aid.
Add other gains of the same category and allowable losses. For relief claims, enter the remaining lifetime limit.

Formula

Ordinary CGT = 18% × taxable gains within the unused UK basic band + 24% × the remainder

The £12,570 Personal Allowance reduces by £1 per £2 of adjusted net income above £100,000. Eligible gross contributions reduce that income and extend the £37,700 basic band. Current-year losses are used first; earlier losses reduce remaining gains only to the £3,000 exemption. BADR and Investors’ Relief charge 14% for 2025/26 and 18% for 2026/27, each subject to its remaining £1 million lifetime limit.

Example

Proceeds of £60,000, basis £25,000 and fees £1,500 produce a £33,500 gain. After the exemption, £30,500 is taxable. Income of £40,000 leaves £10,270 of basic band: £1,848.60 tax at 18% plus £4,855.20 at 24% equals £6,703.80.

Frequently asked questions

Which disposals are supported?

Ordinary gains or gains all qualifying for one selected relief, with normal Personal Allowance and CGT exemption entitlement. Gains exceeding the entered relief limit before losses are rejected conservatively. Mixed relief types, FIG/OWR claims, carried interest, trusts and nonresidents are excluded.

What costs and losses should I enter?

Determine share matching, pooling, allowable improvements and any property relief separately. Use only eligible losses; connected-person restrictions are not calculated. A loss on this disposal is already included, so enter only other losses in the separate field.

When must property tax be paid?

UK residents generally report and pay CGT due on UK residential property within 60 days of completion. Scottish taxpayers use the same UK CGT band. Main-home exemption eligibility is not determined here.

Sources

This tool gives an estimate for general information only. It is not financial, tax, legal or medical advice — check with a qualified professional before you rely on the result.

Last updated: 2026