This calculator works out the capital gains tax on a UK residential property sale using 2026/27 rules: an annual exempt amount of £3,000 (2026/27), tax at 18% within your remaining basic rate band and 24% above it (the basic rate band runs to £50,270 of income in 2026/27), private residence relief for the time you lived there, and your 60-day reporting and payment deadline as an actual calendar date. If your completion date has already passed the deadline, it tells you plainly.
Reviewed by Umer Khan, Senior ManagerLast updated August 2026Figures: 2026/27, sourced from GOV.UK
How to use it
Enter your completion date, sale price and selling costs, then what you paid, your buying costs and any capital improvements (a new roof or an extension, not redecorating).
If the property was ever your main home, enter the months you lived there and the total months you owned it: relief covers your months in residence plus the final 9 months of ownership.
Tick the box if you have already used your £3,000 annual exempt amount (2026/27) this tax year, add your taxable income, and press calculate.
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Calculate your CGT and deadline
Capital Gains Tax · 2026/27
What you'll owe on a property sale — and by when
Enter your figures below to estimate the tax due and your 60-day reporting deadline. Nothing you type leaves your browser.
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2026/27 rates. Not modelled: lettings relief, capital losses, personal allowance taper over £100,000, non-resident rules. Joint owners: use your share only. Sources: GOV.UK: CGT rates and allowances and GOV.UK: report and pay CGT. This is an estimate for general information, not advice.
The 60-day deadline matters more than the rate
UK residents must report and pay CGT on a UK residential property sale within 60 days of completion, using HMRC's online property account. Miss it and penalties and interest follow, even if your Self Assessment return is months away. The calculator prints your exact deadline in large text for that reason. Source: GOV.UK: report and pay Capital Gains Tax.
Assumptions and limits
Figures are correct as at July 2026 and use the rates on GOV.UK: Capital Gains Tax rates and allowances. The calculator does not model:
Lettings relief.
Capital losses brought forward.
The tapering of the personal allowance above £100,000.
Non-resident rules.
Joint owners: run it on your share of everything (typically half), because each owner has their own exempt amount and bands. Estimates only.
Frequently asked questions
HMRC charges late filing penalties and interest on unpaid tax, and the exposure grows the longer the return is outstanding. File as soon as possible even if late; a late return with payment is always better than silence. If you have a reasonable excuse you can appeal a penalty.
The gain is apportioned by time. Months you occupied the property as your main home, plus the final 9 months of ownership regardless of use, are exempt. So a flat owned for 120 months and lived in for 60 gets (60+9)/120 of the gain relieved. Certain absences can also qualify; this calculator models only actual occupation plus the final 9 months.
Since 30 October 2024 the CGT rates on residential property and other assets are unified at 18% and 24% (2026/27). Your taxable gain fills whatever is left of your basic rate band (income up to £50,270 in 2026/27) at 18%; anything above is taxed at 24%. Higher earners therefore usually pay 24% on the whole gain.
Yes. Each owner reports their share of the gain, uses their own £3,000 annual exempt amount (2026/27) and their own rate bands, and files their own 60-day return. Run the calculator once per owner using your share of the sale price, costs and gain.
UK residents generally do not need a 60-day return where no CGT is due, for example a fully relieved main home. You may still need to report the disposal on Self Assessment if you file a return and the proceeds are large enough. Non-residents are different: they must report UK property disposals within 60 days even where no tax is due.
