Capital Gains Tax Calculator UK (2026/27)

To calculate UK Capital Gains Tax for 2026/27: (1) Add up all chargeable gains from disposals during the tax year. (2) Deduct any allowable capital losses from the same year. (3) Subtract your £3,000 Annual Exempt Amount (AEA) — the tax-free allowance for individuals. (4) Stack the remaining taxable gain on top of your taxable income. The portion falling within your unused basic-rate income band (up to a combined total of £50,270) is taxed at 18%; anything above is taxed at 24%.

In the 2026/27 tax year, you pay 18% CGT on gains that fall within your remaining basic-rate income band (where your total taxable income plus gains does not exceed £50,270), and 24% on gains above that threshold. Both rates apply to most assets including second properties. If your taxable income already exceeds £50,270, all of your gains are taxed at 24%. Note: earlier rates of 10%, 20%, 18%, and 28% are now obsolete — the current two rates are 18% and 24%.

For the 2026/27 tax year (6 April 2026 to 5 April 2027), the standard CGT rates are 18% within the basic-rate income band and 24% above it. Qualifying business disposals under Business Asset Disposal Relief (BADR) or Investors’ Relief attract a flat 18% rate on gains up to a £1,000,000 lifetime limit. The previous rates of 10%/20% (assets) and 18%/28% (property) were replaced in October 2024 and 18%/24% have applied since that date.

The Capital Gains Tax annual allowance for individuals in the 2026/27 tax year is £3,000, known as the Annual Exempt Amount (AEA). This is the total amount of gains you can make across all disposals in the tax year before CGT becomes payable. The AEA cannot be carried forward — if unused it is simply lost. Married couples and civil partners each receive their own £3,000 AEA, enabling up to £6,000 of combined annual gains to be sheltered.

Each individual is entitled to make gains of up to £3,000 per tax year free of Capital Gains Tax under the Annual Exempt Amount. Gains on your only or main home are typically fully exempt under Private Residence Relief (PRR), with no monetary ceiling. Additionally, assets held in an ISA wrapper are completely outside the CGT regime — gains and income within ISAs are always tax-free regardless of amount.

The following assets and gains are fully or partially exempt from UK Capital Gains Tax: (1) Your only or main home under Private Residence Relief, provided it has been your principal residence throughout ownership with no exclusive business use. (2) UK government gilts and most corporate bonds. (3) Investments held within an ISA or pension wrapper. (4) Personal possessions (chattels) sold for less than £6,000. (5) Lottery winnings, gifts, and gambling winnings. (6) Gains on cars, even classic cars used for personal enjoyment. (7) Assets transferred between spouses or civil partners in the same household.

CGT on a property sale depends on whether it is your main home or a second or investment property. Your main home is normally exempt in full under Private Residence Relief. For a second or investment property, subtract your purchase price plus permitted costs from your sale proceeds to get the gain, then deduct the £3,000 AEA. The remainder is taxed at 18% on any portion within your remaining basic-rate band and 24% above. For example, a £50,000 gain with £40,000 taxable income produces £27,000 in taxable gain, split £10,270 at 18% (£1,848.60) and £16,730 at 24% (£4,015.20), totalling £5,863.80. UK residential property gains must be reported and paid within 60 days of completion.

Capital gain on a property = Sale proceeds minus (purchase price + enhancement expenditure + costs of acquisition and disposal). Enhancement expenditure includes eligible improvements (e.g. an extension) but not repairs or maintenance. Acquisition and disposal costs include solicitor fees, estate agent fees, and Stamp Duty Land Tax paid on purchase. Private use of the property during ownership and the last 9 months of ownership (whether or not resident) are exempt under Private Residence Relief. Once the net gain is established, deduct the £3,000 Annual Exempt Amount and apply the 18%/24% rates.

There is no minimum holding period to avoid Capital Gains Tax on your main home — you are covered by Private Residence Relief (PRR) as long as the property is your only or main residence throughout the ownership period. The last 9 months of ownership are also always deemed exempt, regardless of residency. For a property that has been a combination of main home and rental or second property, PRR is apportioned by time. No time threshold eliminates CGT on a second home or investment property — you would need to designate it as your main residence and live there for PRR to apply.

Legal strategies to reduce CGT on property disposals include: (1) Designating the property as your main home and living in it (Private Residence Relief). (2) Offsetting allowable capital losses against gains in the same tax year, or bringing forward unused losses registered with HMRC. (3) Utilising both spouses’ or civil partners’ £3,000 AEA by co-owning the asset. (4) Timing the disposal to occur across two tax years to use two years’ Annual Exempt Amounts. (5) Claiming Lettings Relief (up to £40,000) if you have lived in the property and let part of it simultaneously. (6) Deducting all eligible costs: Stamp Duty Land Tax, solicitor fees, estate agency fees, and genuine capital improvements.

You must report UK CGT in two different ways depending on the asset. (1) UK residential property: if the disposal creates a CGT liability, you must report and pay via HMRC’s online Capital Gains Tax on UK Property service within 60 calendar days of the completion date. (2) All other assets (shares, business assets, non-residential property): report through Self Assessment on your annual tax return, due 31 January following the end of the tax year. You must also file if total gains exceed four times the Annual Exempt Amount (£12,000 in 2026/27), even if no tax is due.

Failing to declare a chargeable gain is an offence that can result in HMRC raising a discovery assessment, charging the full tax owed plus interest, and imposing penalties of up to 100% of unpaid tax for deliberate concealment (30% to 100% depending on behaviour). HMRC cross-references Land Registry data, bank records, and estate agency reports to detect undisclosed property gains. The discovery window is 4 years for careless errors and 20 years for deliberate non-disclosure. Taxpayers who voluntarily disclose unprompted errors receive significantly reduced penalty rates.

Yes. HMRC operates extensive cross-referencing programmes to detect undeclared capital gains. For property, HMRC receives automatic notifications from the Land Registry when properties are bought and sold, and compares these against CGT returns and Self Assessment filings. HMRC also has access to foreign tax authority data under the Common Reporting Standard, bank deposit records, and investment platform reporting. Targeted compliance campaigns have focused specifically on rental and second-home property CGT in recent years.

HMRC can normally open an enquiry into CGT returns within 4 years of the end of the tax year in which the return was filed (known as the standard assessment window). For errors made carelessly, HMRC may go back 6 years. For deliberate non-disclosure or fraud, HMRC can investigate up to 20 years retrospectively. Gains that have simply not been reported at all (never appearing in a Self Assessment return) remain vulnerable until the 20-year limit passes from the date the tax became due.

The main legitimate methods of reducing Capital Gains Tax are: (1) Annual Exempt Amount: use your £3,000 per year allowance — it does not carry forward. (2) ISA sheltering: hold assets inside a Stocks & Shares ISA — all gains within an ISA are permanently exempt. (3) Pension contributions: making pension contributions in the year of disposal expands your basic-rate band, shifting more of the gain into the 18% bracket. (4) Spouse/civil partner transfer: transfer assets to your partner before disposal to use both £3,000 allowances and both basic-rate bands. (5) Loss harvesting: deliberately crystallise losses on underperforming assets in the same year to offset gains. (6) BADR or Investors’ Relief: if qualifying, pay a flat 18% on up to £1m of qualifying business gains.

Yes, there are two notable CGT changes from 6 April 2026. First, Business Asset Disposal Relief (BADR) moved to a flat 18% rate (previously 10%, rising to 14% from April 2025, and now 18%). This brings BADR in line with the standard basic-rate CGT band, reducing the benefit compared to the old 10% rate but still lower than the 24% higher-rate CGT. Second, Investors’ Relief also moved to 18%. The standard rates of 18% and 24% — introduced in the Autumn Budget of October 2024 — continue unchanged for 2026/27.

Business Asset Disposal Relief (BADR), formerly Entrepreneurs’ Relief, allows qualifying individuals to pay CGT at a flat 18% rate (from 6 April 2026) rather than the standard 18%/24% rates, on qualifying gains up to a £1,000,000 lifetime limit. Qualifying disposals include: sole trader or business partnership trades that have been run for at least 2 years; shares in a personal trading company where you hold at least 5% of ordinary shares and voting rights and have been an officer or employee for at least 2 years; and EMI share options where conditions are met. Disposals of investment assets, rental property, and shares in investment companies do not qualify.

HMRC receives automatic data feeds from the Land Registry every time a property changes hands in England and Wales (Registers of Scotland and HMRC Stamp Duty records cover Scotland). These feeds include the buyer and seller’s name, the property address, sale price, and completion date. HMRC matches this data against CGT tax returns and Self Assessment filings. Additionally, from 2020 estate agents are required to conduct anti-money laundering checks that can generate reportable information, and from 2016 overseas buyers have been required to register with HMRC. A sale that is not reported is therefore very likely to be detected.