Work out which rules apply
Tax treatment depends on ownership, residence history, use and the seller’s status. Individuals, estates, trusts and companies do not all use the same rates, allowances or reporting rules.
A property inherited by a beneficiary and sold later is different from an estate selling during administration. Ask an adviser which taxpayer has the gain and which value is the starting point.
Calculate the gain before applying tax
Start with proceeds and the relevant acquisition value, then consider allowable costs, losses and applicable reliefs. A mortgage balance is not itself deducted when calculating a capital gain.
For individuals, the annual exempt amount is shared across gains, not available separately for each property. Income and taxable gains interact with the tax bands; a single basic-rate percentage can understate tax.
Check residence relief and reporting
Private Residence Relief has conditions. Do not assume owning only one property or calling it your home establishes a full exemption; occupation and use need checking.
UK residents with CGT to pay on a UK residential property sale generally have a 60-day reporting and payment deadline after completion. Non-resident obligations differ. Check HMRC’s current guidance before completing.
Use the calculator within its limits
Our individual calculator is a simplified illustration and assumes the allowance is unused. It does not fully calculate band crossing, shared ownership, losses, reliefs or estate tax.
Get an adviser’s calculation if the liability affects whether you can afford the sale. Keep acquisition, improvement, disposal and estate-valuation records.
Sources & review
Last reviewed:
Simplified individual estimate for 2026/27. Assumes the full £3,000 allowance is unused; excludes losses, other gains, ownership shares and reliefs. Basic-rate mode applies 18% to all taxable gain and may underestimate tax: part may be taxed at 24% when income plus gains exceeds the basic-rate band. Not suitable for estates, trusts or companies.
- HMRC — Capital Gains Tax rates
Individuals: 18% within the available basic-rate band and 24% above it; taxable income and gains must be considered together.
- HMRC — CGT allowances
The individual's annual tax-free allowance is £3,000; it is shared across gains for the tax year, not per property. Trusts have different rules.
- HMRC — Tax when you sell your home
Private Residence Relief can exempt a qualifying main home; second homes and let properties may create a taxable gain. Relief has conditions.
- HMRC — Reporting and paying CGT
UK residents with CGT to pay on a UK residential sale generally must report and pay within 60 days of completion. Non-resident reporting obligations differ.
Review dates record our source check, not the date a rule took effect. Rules can change; check the linked guidance before acting. Legal processes differ across the UK.