Capital Gains Tax on Property Calculator (2026/27)

Work out your property CGT in seconds

Use the calculator above to estimate your bill: enter what you paid, what you're selling for, your buying and selling costs, any capital improvements, and your other taxable income for the year. The tool stacks the gain on top of your income to split it correctly between the 18% and 24% rates. Treat the result as a planning estimate, then confirm the exact figure on your Self Assessment return or 60-day property report.

How the capital gains tax on property calculation works

Capital Gains Tax on residential property is charged on your profit, not the sale price. The basic formula is straightforward:

Taxable gain = Sale price − Purchase price − Allowable costs − Annual Exempt Amount

Allowable costs are the things you actually spent acquiring, improving and selling the property: stamp duty paid when you bought, solicitor and estate agent fees, survey fees, and capital improvements such as an extension or a new kitchen where there wasn't one before. Routine repairs and mortgage interest don't count here (interest is a rental-expense matter, not a capital cost).

For 2026/27 the Annual Exempt Amount (AEA) is £3,000 per person. That slice of gain is tax-free. Whatever's left is your taxable gain, and the rate depends on where it sits once added to your income:

• 18% on the part of the gain that falls within your remaining basic-rate band;
• 24% on the part above the basic-rate band.

The basic-rate band runs to £37,700 of taxable income (income after your Personal Allowance). To work out how much room is left, take £37,700 and subtract your taxable income. The gain fills that gap at 18%, and anything beyond it is taxed at 24%. These residential rates were aligned at 18% and 24% from 30 October 2024, so the same figures apply whether you sell a buy-to-let or other chargeable assets.

One point that trips people up: CGT is a UK-wide tax, so the 18% and 24% rates and the £37,700 band apply the same way in Scotland, Wales, England and Northern Ireland. Even if you pay Scottish income tax on your salary, your CGT band still uses the UK £37,700 figure, not the Scottish bands. Your general capital gains tax position on shares and other assets uses the same rates and the same single £3,000 allowance shared across all your gains for the year.

Worked example: a landlord selling a buy-to-let

Priya bought a flat in 2014 for £180,000 and is selling it in 2026 for £290,000. Over the years she added a loft conversion costing £14,000, and her combined legal and estate agent fees on purchase and sale come to £6,000. She earns £35,000 from her job.

• Gross gain: £290,000 − £180,000 = £110,000
• Less allowable costs: £14,000 + £6,000 = £20,000 → gain £90,000
• Less Annual Exempt Amount: £90,000 − £3,000 = £87,000 taxable gain

Now stack it on her income. Her taxable income is £35,000 − £12,570 Personal Allowance = £22,430. Her remaining basic-rate band is £37,700 − £22,430 = £15,270.

• £15,270 taxed at 18% = £2,748.60
• £87,000 − £15,270 = £71,730 taxed at 24% = £17,215.20
• Total CGT = £19,963.80

Worked example: a higher-rate taxpayer's second home

Tom earns £60,000 and sells a second home he bought for £150,000 at £200,000. His buying and selling costs were £4,000.

• Gain: £200,000 − £150,000 − £4,000 = £46,000
• Less AEA: £46,000 − £3,000 = £43,000 taxable gain

Tom's taxable income (£47,430 after the Personal Allowance) already exceeds £37,700, so he has no basic-rate band left. The whole gain is taxed at 24%: £43,000 × 24% = £10,320. Because his gain pushed nothing into a lower band, there's no 18% slice at all.

2026/27 CGT rates and thresholds for residential property

Figures checked against HM Revenue & Customs for the 2026/27 tax year. See the official guidance at gov.uk Capital Gains Tax rates and the reporting rules at gov.uk report and pay CGT. For free, impartial help understanding your options, MoneyHelper is a good starting point.

The 60-day reporting deadline you can't miss

When you sell UK residential property at a gain, you usually have to report and pay the CGT within 60 days of completion using HMRC's online property account, not just on your annual return. Miss it and penalties and interest start to build. If you also file Self Assessment, you still include the disposal there and the 60-day payment is credited against the final bill. Our 60-day CGT reporting calculator helps you check the deadline and the amount due.

How to legally reduce your property CGT bill

• Use both spouses' allowances. If the property is jointly owned, each owner has their own £3,000 AEA and their own bands. Transferring a share to a spouse or civil partner before sale is normally tax-neutral and can move part of the gain into a lower band.
• Claim every allowable cost. Dig out completion statements, improvement invoices and the stamp duty you paid on purchase. People routinely forget the SDLT, LBTT or LTT they paid when buying, which is fully deductible.
• Claim Private Residence Relief if you ever lived there. If a property was once your only or main home, the years you lived in it (plus the final 9 months) are exempt. Letting Relief may also apply in limited cases.
• Offset losses. Capital losses on other assets in the same year, or carried forward, reduce the taxable gain before the AEA.
• Time the disposal. Gains are taxed in the year of completion. Spreading two disposals across two tax years gives you two £3,000 allowances.

If you're weighing up whether to keep letting the property, our buy-to-let profit calculator and the Section 24 mortgage-interest relief calculator show the ongoing rental position alongside the one-off CGT.

Common mistakes people make with property CGT

• Taxing the whole sale price. CGT applies to the gain, not the price you sell for. The purchase price and costs come off first.
• Forgetting the 60-day clock. The deadline runs from completion, not from filing your tax return the following January.
• Assuming the main home is always exempt. Private Residence Relief is generous but not automatic on a second home or a buy-to-let you never lived in.
• Mixing up repairs and improvements. A repaired roof is a rental expense; a new extension is a capital cost. Only the capital improvement reduces the gain.
• Applying Scottish income-tax bands to the gain. CGT uses the UK £37,700 basic-rate band everywhere, even for Scottish taxpayers.
• Ignoring the order of stacking. The gain sits on top of income, so a modest salary plus a big gain can still push most of the gain to 24%.

These figures are estimates for guidance only and not personal tax or financial advice. Your own circumstances, reliefs and exact dates can change the result, so check with HMRC or a qualified adviser before acting.

Related calculators

Carry on planning with our rental income tax calculator to work out tax on the rent itself, the second-home stamp duty calculator for what you'd pay buying another property, and the capital gains tax calculator for gains on shares and other assets.