Hundred SummersCapital gains tax on a property sale: second homes, buy-to-lets and former homes
Costs and improvements off the gain, private residence relief for the months it was your home plus the final nine, the £3,000 exemption per owner, then the residential rates stacked on your other income, and the 60-day deadline. Your figures never leave your browser.
Loading the calculator… (requires JavaScript; your figures never leave your browser)
Worked example
Computed when this page was built by the same engine that runs the calculator above, so the figures below and the live tool can never disagree. Change any input above to see your own.
| Inputs | |
|---|---|
| Sale / purchase price | £400,000 / £250,000 |
| Buying, selling and improvement costs | £20,000 |
| Owned / lived in as main home | 120 / 60 months |
| Owners | One |
| Other taxable income | £40,000 |
| Results | |
|---|---|
| Gain after costs | £130,000 |
| Private residence relief (69 of 120 months) | £74,750 |
| Chargeable gain | £55,250 |
| Taxable after the £3,000 exemption | £52,250 |
| Capital gains tax | £11,924 |
| Report and pay within | 60 days of completion |
The next question
Would downsizing free money for retirement? →Downsizing calculator
Or answer it with everything else: the full Hundred Summers plan connects your pay, pensions, savings, property, tax and spending year by year, and stress-tests them across 500 simulated market histories.
Read the guide
- Buy-to-let in 2026: the tax, the surcharge, and the sale →Section 24 explained with real numbers, why a higher-rate landlord can lose money on a property that makes a cash profit, plus the additional-property stamp duty, the April 2027 surcharge, and capital gains tax when you sell.
What is deducted, what is relieved, what is taxed
Start from sale price minus purchase price. Deduct the costs of buying and selling (stamp duty, legal fees, agents, surveys), and improvements: extensions and conversions, not repairs or redecoration. Then private residence relief exempts the fraction of the gain for the months the property was your main home, plus the final nine months of ownership regardless. What remains is the chargeable gain; each owner takes off their own £3,000 annual exempt amount, and the residential rates apply: 18% for as much of the gain as fits in your remaining basic-rate band, 24% above.
The traps
The 60-day return and payment deadline after completion catches people who assume it waits for the tax return. Married couples and civil partners can transfer a share before sale to use two exemptions and two basic-rate bands, but only genuinely. Inherited property takes its probate value as the base cost, gifts to anyone but a spouse are disposals at market value, and a property that was your home only part of the time needs the dates right. A landlord’s ongoing tax is the rental income tax calculator’s job; shares and funds go through the general CGT calculator; the Hundred Summers app carries property disposals through the plan with the tax in the year it falls.
Sources
- HMRC, Tax when you sell property (the 60-day return) and work out your gain.
- HMRC, Private Residence Relief.
- HMRC, Capital Gains Tax rates and allowances.