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 whatever is left of your basic rate band and 24% above it (the basic rate band covers the first £37,700 of taxable income, which is your income after the personal allowance), private residence relief for the months you lived there taken together with the last 9 months of ownership, 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.
Figures checked 5 September 2026Last updated September 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 (improvement work such as an extension or a loft conversion, not repairs, maintenance or decorating). Work you have already claimed as a repair against rental income cannot also be deducted here.
If the property was ever your main home, enter the months you lived there, the months between moving out and completion (0 if you still lived there when you sold), and the total months you owned it. Relief covers the months you lived there taken together with the last 9 months of ownership, which qualify in any event.
Tick the box if you have already used your £3,000 annual exempt amount (2026/27) this tax year, add your total income before tax, 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.
The day the sale completed. The 60-day deadline applies to completions on or after 27 October 2021.
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Salary, self-employment profit, rental profit and pension, before your personal allowance.
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What you paid, or the market value when you inherited it or were given it.
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Improvement work such as an extension or a loft conversion. Not repairs, maintenance or decorating. Work already claimed as a repair against rental income cannot be deducted here as well.
Months you actually lived there as your only or main home. Leave at 0 if it never was.
Enter 0 if you still lived there when you sold. The last 9 months of ownership always qualify, so this decides whether they add anything.
Purchase to completion. If you owned it before 31 March 1982, count from 31 March 1982.
2026/27 rates, figures checked 5 September 2026. Not modelled: lettings relief; capital losses in this tax year or brought forward; periods of absence that can still count as occupation (working abroad, up to four years of job-related absence, and up to three years for any reason, TCGA 1992 s.223(3)); up to 24 months before you moved in where the delay was construction, renovation, redecoration or alteration, or the sale of your previous main home (TCGA 1992 s.223ZA); the 36-month final period that can apply where the owner is a disabled person or a resident in a care home (TCGA 1992 s.225E); partial use of the annual exempt amount (the tick box treats it as either fully available or fully used); business use of part of the property and gardens or grounds over half a hectare (TCGA 1992 s.222(2)); pension contributions and Gift Aid, which can widen the basic rate band; property owned before 31 March 1982; trusts, personal representatives and non-resident rules. The months you lived there are treated as one unbroken block ending when you moved out, so a second, later spell of residence is not counted. Joint owners: use your share only. Sources: GOV.UK: CGT rates and allowances, HMRC helpsheet HS283: private residence relief 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 5 September 2026 and use the rates on GOV.UK: Capital Gains Tax rates and allowances. The list below is a summary; the note under the calculator carries the full list of what it does not model. 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. The exempt fraction is the months the property was your only or main home, taken together with the last 9 months of ownership in any event, divided by the total months you owned it. The two periods are combined, not added up. Where you were still living there in the last 9 months, those months are already counted once and are not counted twice. Where you lived there for fewer than 9 months, the last 9 months still qualify on their own.
A flat owned for 120 months, lived in for the first 60 and let for the last 60, is relieved on 69/120 of the gain. The same flat lived in for the last 60 months up to the sale is relieved on 60/120. A flat owned for 120 months and lived in only for the last 4 is relieved on 9/120, because the last 9 months qualify whatever the property was used for in them. Certain absences can also count as occupation; this calculator models only actual occupation and the last 9 months. Source: TCGA 1992 s.223(2) and HMRC helpsheet HS283.
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 at 18%; anything above is taxed at 24%. The basic rate band covers the first £37,700 of taxable income, which is your income after the personal allowance, so the gain is taxed as the top slice of your income. 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.
