Capital Gains Tax on Property Calculator United Kingdom

Selling a second home or a buy-to-let property in the UK almost always brings a Capital Gains Tax bill, because Private Residence Relief only covers the home you live in. This calculator applies the 2026/27 rates to your gain, takes off the annual exempt amount and uses your other income to work out how much is taxed at 18% and how much at 24%.

How the gain is worked out

The gain is your profit, not the sale price. Take what you sold the property for, subtract what you paid and then subtract your allowable costs: legal and estate agent fees on the purchase and the sale, the Stamp Duty you paid when buying, and the cost of capital improvements such as an extension or a loft conversion. Everyday repairs and redecoration do not count, and neither does mortgage interest, which is a cost of borrowing rather than of the asset. What is left is the chargeable gain.

The annual exempt amount

Every individual has an annual exempt amount, £3,000 for 2026/27. You deduct it from your total gains for the tax year before tax is calculated, so a £95,000 gain becomes £92,000 taxable. The allowance is per person, so a couple who own a property jointly can use two allowances against the same sale. It cannot be carried forward, which is one reason spreading disposals across tax years can help. The calculator lets you enter any part of the allowance you have already used against other gains, so it is not counted twice.

Why your income decides the rate

Capital Gains Tax on residential property has two rates, 18% and 24%, and which applies depends on how much of your basic rate Income Tax band is still free. The basic rate limit is £50,270. The calculator compares it with your other taxable income (or the £12,570 personal allowance, if that is higher) to find the band left. The part of the gain that fits inside it is taxed at 18% and the rest at 24%. A higher rate taxpayer whose income is already above £50,270 has no band left, so the whole gain is taxed at 24%.

A worked example

You bought a buy-to-let flat for £200,000 and sell it for £300,000, with £5,000 of buying, selling and improvement costs. The gain is £95,000. After the £3,000 annual exempt amount, £92,000 is taxable. Your other income is £40,000, so £10,270 of the basic rate band remains. That slice of the gain is taxed at 18%, which is £1,848.60, and the remaining £81,730 at 24%, which is £19,615.20. The total Capital Gains Tax is £21,463.80. With income of £50,270 or more, all £92,000 would be taxed at 24%.

The 60-day reporting deadline

You must report the disposal and pay the tax within 60 days of completion through HMRC’s online UK property reporting service. This is separate from, and usually well before, your Self Assessment return. Miss the deadline and HMRC charges late filing penalties and interest, even if you later pay in full. Estimate the bill as soon as a sale is agreed so the cash is set aside and the return goes in on time.

Assumptions and limitations

This is a planning estimate, not advice or an HMRC computation. It uses the 2026/27 annual exempt amount, CGT rates and basic rate limit, stored as parameters sourced from gov.uk and reviewed each tax year. It assumes the property is wholly a second home or investment with no Private Residence Relief, that one individual is selling rather than a couple or a company, and that this is your only gain using up the annual exempt amount and the basic rate band. It does not model letting relief, part-period main residence relief, losses brought forward, or gains in a trust or company. For a large or complex sale, confirm the figures with an accountant before you file.

About This Tool: Capital Gains Tax on Property

Capital gains tax on property: use this tool to get an instant, accurate estimate. The figures follow official GOV.UK guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.