Your Complete Guide to UK Capital Gains Tax in 2026
Few areas of personal finance generate as much confusion as UK capital gains tax. People understand income tax instinctively, you earn money, the government takes a slice. But CGT operates differently, applies to a wide range of assets, and carries its own set of rates, thresholds, reliefs, and deadlines that shift with each Budget. Getting it wrong is expensive. Getting it right, with some forward planning, is entirely manageable.
This guide covers everything you need to know about UK capital gains tax as it stands in 2026, from the fundamental mechanics to the practical strategies that reduce your exposure legally and efficiently.
How UK Capital Gains Tax Actually Works
UK capital gains tax is charged on the profit, the gain, you make when you dispose of an asset that has increased in value since you acquired it. The tax is not applied to the full sale proceeds but to the difference between what you paid and what you received, adjusted for allowable costs.
A disposal is a broader concept than most people assume. Selling an asset is the most obvious trigger, but gifting an asset, exchanging one asset for another, receiving compensation for an asset’s loss or destruction, and transferring an asset to a trust all count as disposals for CGT purposes. The only major exception is transfers between spouses and civil partners who live together, which HMRC treats as taking place at a value that produces neither a gain nor a loss.
The Base Cost and What You Can Deduct
Your base cost is the starting point for any CGT calculation. It typically equals the amount you originally paid for the asset, including incidental acquisition costs such as legal fees, broker commissions, and stamp duty land tax on property purchases. You can also add the cost of capital improvements made during your period of ownership, work that genuinely enhances the asset’s value rather than simply maintaining it in its existing condition.
On the disposal side, you can deduct the costs of sale from your proceeds before arriving at the chargeable gain. Estate agent fees, solicitor charges, and selling commissions all reduce the figure that enters the UK capital gains tax calculation. Keeping complete records of every cost associated with an asset from the moment you acquire it to the moment you dispose of it is the single most straightforward way to ensure you never pay CGT on more than you genuinely owe.
UK Capital Gains Tax Rates in 2026
The rate of UK capital gains tax that applies to your gain depends on two variables: the nature of the asset and where your gains sit relative to your income tax bands in the year of disposal.
For most chargeable assets, including shares, investment funds held outside an ISA, and non-residential property, the CGT rate is 18% for gains that fall within the basic rate band and 24% for gains that exceed it. These rates apply from 30 October 2024 following the Autumn Budget, which aligned the rates for shares and investment assets more closely with residential property rates.
Residential property that does not qualify for Private Residence Relief is taxed at 18% within the basic rate band and 24% above it, the same rates that have applied since April 2024 when the higher residential rate was reduced from 28%.
Business Asset Disposal Relief in 2026
Business Asset Disposal Relief (BADR) remains available for qualifying business disposals, though the rate changed significantly from April 2025. Gains that qualify for BADR are taxed at 14% for disposals made in 2025/26, rising to 18% from April 2026 onwards. The lifetime limit remains £1 million. To qualify, you must have owned the business and worked in it as an employee or officer for at least two years prior to disposal.
Investors’ Relief, which applies to external investors in unlisted trading companies, follows a similar trajectory, with its rate also rising to 18% from April 2026, subject to a £1 million lifetime limit.
How HMRC Stacks Gains Against Your Income
HMRC does not assess your capital gains in isolation. It adds your net taxable gains to your total income for the tax year and determines which CGT rate applies based on where the combined figure falls relative to the basic rate band threshold of £50,270. Gains that sit within the band attract the lower rate; gains that push above it attract the higher rate.
This stacking rule has a direct bearing on timing decisions. If your income is lower in one tax year than another, perhaps because you have retired, reduced your working hours, or made significant pension contributions, disposing of an asset in that lower-income year can reduce the rate of UK capital gains tax you pay on the same gain.
The Annual CGT Exempt Amount in 2026
Every UK resident individual receives an annual exempt amount, a threshold of gains that attracts no UK capital gains tax. For 2025/26 and 2026/27, this allowance stands at £3,000. The allowance cannot be carried forward to future tax years, so any portion that goes unused is simply lost.
Married couples and civil partners each receive their own annual exempt amount, allowing a household to shelter up to £6,000 of combined gains from CGT each year. Given the reduction from the previous £12,300 allowance in 2022/23, the importance of deliberate annual planning has grown considerably. Disposals that would once have sat comfortably below the threshold now frequently generate taxable gains.
Applying Losses Against the Exempt Amount
Capital losses must be set against gains in the tax year they arise before the annual exempt amount is applied. This sequencing matters because using losses to reduce gains below the exempt amount effectively wastes those losses, the exempt amount would have covered the gains anyway. Where possible, timing the crystallisation of losses to coincide with years when your gains substantially exceed the exempt amount produces the most efficient outcome for UK capital gains tax purposes.
Key Reliefs That Reduce or Defer UK Capital Gains Tax
The UK capital gains tax system includes several reliefs that can substantially reduce the tax you owe or defer it to a future date. Knowing which ones apply to your situation is essential before completing any significant disposal.
Private Residence Relief
Private Residence Relief (PRR) exempts the gain on your main home from UK capital gains tax, covering the entire period of residence plus the final nine months of ownership. Where a property has not always been your main residence, for example, if you moved out and rented it, the gain is apportioned between qualifying and non-qualifying periods, with only the latter attracting CGT.
Gift Hold-Over Relief
When you give away a qualifying business asset or certain other assets, you can elect to hold over the gain rather than paying CGT immediately. The recipient takes on your original base cost, and the gain crystallises only when they eventually sell. This makes Gift Hold-Over Relief particularly useful for passing business assets to the next generation as part of succession planning.
Rollover Relief
Business owners who sell a qualifying asset and reinvest the proceeds in another qualifying asset within three years can defer the UK capital gains tax charge under Rollover Relief. The deferred gain is rolled into the base cost of the replacement asset and becomes payable only when that asset is ultimately sold without reinvestment. The relief supports business growth by removing the tax friction from asset upgrades.
Enterprise Investment Scheme Deferral Relief
Investing the proceeds of a disposal into shares that qualify under the Enterprise Investment Scheme (EIS) allows you to defer UK capital gains tax on the original gain until the EIS shares are sold. The deferred gain can also be further deferred if the proceeds from the EIS sale are reinvested into another qualifying EIS company. For investors comfortable with the risks of early-stage companies, advisers such as Spice Taxation often highlight this relief as a mechanism to keep capital working without an immediate CGT charge.
Reporting and Paying UK Capital Gains Tax
The reporting route for UK capital gains tax depends on the type of asset involved.
For UK residential property, HMRC requires you to file a return and pay any CGT owed within 60 days of the completion date. This is handled through HMRC’s online property CGT service and runs independently of your annual Self Assessment return. The 60-day rule applies even where no tax is owed, in most circumstances where CGT could theoretically have arisen.
For all other chargeable asset disposals, CGT is reported through Self Assessment. Gains must be declared on your tax return for the relevant tax year, with payment due by 31 January following the end of that tax year. Late filing and late payment each attract automatic penalties, and interest accrues on unpaid tax from the payment deadline.
Record-Keeping Requirements
HMRC expects you to retain records supporting your CGT calculations for at least 22 months after the end of the tax year for income tax purposes, and significantly longer for assets held over many years where the acquisition predates the disposal by decades. Share certificates, conveyancing documents, improvement invoices, and disposal correspondence all form part of the evidence base HMRC may request on enquiry.
Conclusion
UK capital gains tax touches a remarkably broad range of financial decisions, from selling shares and investment property to transferring business assets and gifting to family members. The 2026 landscape brings updated rates for most asset classes, a compressed annual exempt amount, and evolving relief structures that require careful navigation.
The common thread across every effective CGT strategy is the same: planning before the disposal, not after. Understanding how the rates are calculated, which reliefs are available, and how the annual allowance interacts with losses gives you the tools to make genuinely informed decisions. Where the sums are substantial, a qualified tax adviser adds far more value than their fee, and the alternative is often paying more UK capital gains tax than the law actually requires.
