UK Capital Gains Tax Calculator
Calculate your CGT liability on property, shares, crypto and other assets for 2025/26
CGT Calculation Breakdown
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2025/26 CGT Rates
| Asset Type | Basic Rate (18%) | Higher Rate (24%) | Special Rate |
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Available CGT Reliefs
Scenario Comparison
| Scenario | Taxable Gain | CGT Due | Effective Rate |
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UK Capital Gains Tax Calculator – Complete Guide to CGT Rates, Reliefs and Allowances
Capital Gains Tax (CGT) is one of the most misunderstood taxes in the UK tax system, yet it affects hundreds of thousands of taxpayers each year. Whether you are selling a buy-to-let property, disposing of shares, crystallising cryptocurrency gains, or passing on valuable assets, understanding how CGT works is essential for effective tax planning. The 2025/26 tax year brings significant changes following the October 2024 Budget, with the annual exempt amount now reduced to just £3,000 and main CGT rates harmonised at 18% and 24%. This comprehensive guide explains everything you need to know about calculating, reporting, and potentially reducing your Capital Gains Tax liability.
The UK Capital Gains Tax system operates on the principle that profits from disposing of assets should contribute to the public purse. However, the tax is charged only on the gain you make, not the total sale proceeds, and numerous reliefs and exemptions exist to reduce or eliminate your liability in certain circumstances. From Private Residence Relief that protects your main home to Business Asset Disposal Relief for entrepreneurs, the CGT rules reward those who understand them. Our calculator above helps you estimate your CGT liability across different asset types, taking into account your income tax band, available reliefs, and the current 2025/26 rates.
Understanding Capital Gains Tax in the UK
Capital Gains Tax applies when you dispose of an asset that has increased in value during your period of ownership. The term “disposal” extends beyond simple sales to include gifts, exchanges, receiving compensation for damaged or destroyed assets, and transferring assets to a company. However, not every disposal triggers a CGT charge. Your main residence is typically exempt through Private Residence Relief, transfers between spouses and civil partners occur on a “no gain, no loss” basis, and certain assets like ISA investments and gilts are entirely exempt from CGT.
The tax operates differently from Income Tax in several important ways. While your salary, pension, and rental income are taxed in the year they arise, CGT is only payable when you actually dispose of an asset. This means you could hold appreciating assets for decades without paying any tax, only triggering a liability when you choose to sell. This characteristic makes CGT particularly important for tax planning, as the timing of disposals can significantly affect your overall tax position. Understanding when to realise gains, how to utilise your annual exemption effectively, and which reliefs might apply to your situation can save substantial amounts in tax.
The annual exempt amount has been slashed from £12,300 in 2022/23 to just £3,000 for 2025/26. This dramatic reduction means many more taxpayers will face CGT charges on gains that would previously have been tax-free. Married couples and civil partners each have their own £3,000 allowance, allowing combined tax-free gains of £6,000.
CGT Rates for 2025/26 Tax Year
Following the October 2024 Budget, Capital Gains Tax rates were harmonised across all asset types from 6 April 2025. Previously, residential property attracted higher rates than other assets, but now all gains are taxed at either 18% for basic rate taxpayers or 24% for higher and additional rate taxpayers. The rate you pay depends on your total taxable income plus your gains. If the combined figure keeps you within the basic rate band (up to £37,700 above your personal allowance), you pay 18%. Any gains that push you into higher rate territory attract the 24% rate.
This means that if you have taxable income of £20,000 and a gain of £15,000 (after deducting the £3,000 annual exemption, leaving £12,000), your combined total is £32,000. Since this falls within the basic rate band, you would pay CGT at 18% on the entire gain. However, if your taxable income were £45,000, your combined total would be £57,000, meaning part of your gain falls within the basic rate band and part in the higher rate band. In this scenario, you would pay 18% on the portion within basic rate and 24% on the remainder. The calculation can become complex when multiple disposals occur in the same tax year.
If exceeds £37,700: Split calculation required at 18% and 24%
Business Asset Disposal Relief (BADR)
Business Asset Disposal Relief, formerly known as Entrepreneurs Relief, provides a reduced CGT rate for qualifying business disposals. From 6 April 2025, the BADR rate is 14%, rising to 18% from April 2026. This relief is designed to encourage entrepreneurship by ensuring that business owners keep more of their proceeds when selling their business or shares in their trading company. The lifetime limit for BADR remains at £1 million of qualifying gains, meaning you could potentially save significant tax compared to standard CGT rates if you qualify.
To qualify for BADR, you must meet specific conditions depending on whether you are disposing of a business, shares, or assets following business cessation. For share disposals, you must have been an officer or employee of the company, held at least 5% of ordinary share capital with 5% voting rights, and met these conditions for at least two years before disposal. The company must be a trading company rather than an investment company. Similar qualifying conditions apply to sole traders and partners disposing of their business interests. Given the complexity of these rules and the significant tax savings available, professional advice is strongly recommended before claiming BADR.
Calculating Gains on Residential Property
Residential property remains one of the most common triggers for Capital Gains Tax, particularly for landlords selling buy-to-let investments or individuals disposing of second homes. The calculation begins with the sale price and deducts the original purchase price plus all allowable costs. These costs include solicitors fees on both purchase and sale, estate agent fees, stamp duty land tax paid on purchase, and the cost of any improvements that enhanced the property value. Importantly, maintenance and repair costs are not allowable deductions for CGT purposes, as these are revenue expenses rather than capital enhancements.
For properties purchased before 31 March 1982, the base cost for CGT purposes is the market value at that date rather than the original purchase price. This rebasing rule means any gain arising before April 1982 escapes CGT entirely. Additionally, if you purchased a property before December 2017 and it was never your main residence, you may be entitled to indexation allowance for the period of ownership up to December 2017, which adjusts the base cost for inflation. These rules can significantly reduce your taxable gain on long-held properties.
UK residents must report and pay CGT on residential property sales within 60 days of completion, even if they normally complete a Self Assessment return. Late reporting triggers automatic penalties of £100, with interest charged on any tax paid late. Use the HMRC Property Disposal Service to report and pay.
Private Residence Relief Explained
Private Residence Relief (PRR) is the most valuable CGT relief for most taxpayers, potentially exempting the entire gain on your main home from tax. If you have lived in a property as your only or main residence throughout your ownership, never let any part of it, never used any part exclusively for business, and the grounds do not exceed 0.5 hectares, you qualify for full PRR and pay no CGT when you sell. However, if any of these conditions are not met, you may have a reduced entitlement to relief or no entitlement at all.
The relief is calculated on a time-apportionment basis when you have not occupied the property as your main residence throughout ownership. The proportion of the gain eligible for relief equals the period of qualifying occupation divided by the total period of ownership. Importantly, the final nine months of ownership always qualify for relief provided you lived in the property as your main residence at some point. This “final period exemption” was reduced from 18 months in April 2020 and provides a useful planning opportunity when leaving a former home. For disabled individuals or those in long-term care, the final period extends to 36 months.
Lettings Relief and When It Applies
Lettings Relief provides additional CGT relief when you let out all or part of a property that qualifies for some Private Residence Relief. However, since April 2020, the relief is severely restricted and now only applies when you were in shared occupation with your tenant. This means letting out a spare room while you continue to live in the property as your main home. Letting out an entire property after moving out no longer qualifies for Lettings Relief under the current rules, even if it would have qualified under the pre-2020 regime.
Where Lettings Relief does apply, it is capped at the lowest of three amounts: the amount of Private Residence Relief you receive, the gain attributable to the letting, or £40,000 (£80,000 for married couples or civil partners disposing jointly). In practice, this relief is now relevant mainly for those who take in lodgers while living in their main home. The restriction of Lettings Relief caught many landlords by surprise and increased CGT liabilities significantly for those selling former homes that had been let after moving out. Understanding these changes is crucial for anyone planning to sell property that has been let at any time during ownership.
CGT on Shares and Investments
Shares and other securities attract standard CGT rates of 18% and 24% when disposed of outside tax-advantaged wrappers like ISAs and pensions. The challenge with share disposals often lies in calculating the base cost, particularly when shares have been acquired over multiple purchases, through dividend reinvestment schemes, or following corporate actions like share splits, mergers, and bonus issues. The share matching rules determine which shares you are treated as disposing of when you sell only part of your holding.
Under the current share matching rules, disposals are matched first against shares acquired on the same day as the disposal, then against shares acquired within the following 30 days (the “bed and breakfasting” rule), and finally against your section 104 holding. The section 104 holding is a pooled average of all other shares of that class, with the base cost being the pooled average cost per share. This pooling mechanism simplifies calculations for long-standing holdings but requires careful record-keeping of acquisition costs, dates, and subsequent corporate events that affect your holding.
Cryptocurrency and Digital Assets
HMRC treats cryptocurrency as property for tax purposes, meaning disposals of Bitcoin, Ethereum, and other digital assets are subject to Capital Gains Tax in the same way as shares or property. Every disposal creates a potentially taxable event, including selling crypto for traditional currency, exchanging one cryptocurrency for another, using crypto to pay for goods or services, and giving away crypto to anyone other than a spouse or civil partner. The volatile nature of cryptocurrency prices can create substantial gains or losses even over short holding periods.
Calculating CGT on cryptocurrency can be particularly complex due to the frequency of transactions and the challenges of establishing base costs for assets acquired through multiple purchases, mining, staking rewards, or airdrops. HMRC expects taxpayers to maintain detailed records of every acquisition and disposal, including dates, quantities, and values in pounds sterling at the time of transaction. Various cryptocurrency tax calculation tools exist to help aggregate transaction data and apply the share matching rules, but ultimately the responsibility for accurate reporting rests with the taxpayer.
Exchanging one cryptocurrency for another is a disposal for CGT purposes, potentially triggering a tax liability even though you have not received any traditional currency. The gain is calculated as the sterling value of the crypto received minus your base cost in the crypto disposed of.
Allowable Costs and Deductions
Maximising your allowable cost deductions is essential for minimising CGT liability. Allowable costs fall into several categories: acquisition costs (purchase price plus incidental costs like legal fees and stamp duty), enhancement expenditure (capital improvements that enhanced asset value and are still reflected in the asset at disposal), costs of establishing, preserving or defending title, and disposal costs (legal fees, agent fees, advertising costs). All these costs reduce your chargeable gain and therefore your tax liability.
It is crucial to distinguish between allowable capital expenditure and disallowable revenue expenditure. For property, building an extension, installing a new kitchen or bathroom, and adding a conservatory are typically allowable improvements. However, repairing a roof, redecorating, or replacing like-for-like items are maintenance costs that cannot be deducted for CGT purposes, although they may be deductible against rental income for Income Tax purposes. Keeping detailed records and receipts for all expenditure is essential, as HMRC may request evidence to support claimed deductions.
Using Losses to Reduce Your CGT Bill
Capital losses arise when you dispose of an asset for less than its allowable cost. These losses can be set against capital gains in the same tax year to reduce your overall CGT liability. If losses exceed gains in a year, the excess can be carried forward indefinitely and set against gains in future years. However, losses can only be set against gains, never against income, and certain restrictions apply to losses on assets sold to connected persons or where artificial arrangements are involved.
Strategic loss realisation is a legitimate tax planning technique. If you have investments showing losses, selling them before the end of the tax year crystallises those losses for offset against gains. You must be careful of the “bed and breakfasting” rules though: if you sell shares and buy them back within 30 days, the loss is not allowable. A common workaround is the “bed and spouse” strategy, where one spouse sells shares at a loss and the other spouse immediately purchases identical shares. Alternatively, waiting 31 days before repurchasing or buying similar but not identical investments can achieve the same result within the rules.
Annual Exempt Amount Planning
The £3,000 annual exempt amount provides valuable CGT-free disposal capacity that is lost if not used each year. For investors with substantial unrealised gains, making annual disposals to utilise the exemption can crystallise gains tax-free over time. This strategy is particularly effective when combined with ISA contributions: selling £3,000 of gains outside an ISA and reinvesting within your ISA allowance achieves the dual benefits of using your CGT exemption and sheltering future growth from tax.
Married couples and civil partners should consider transferring assets between themselves before disposal to utilise both annual exemptions. Since inter-spouse transfers occur on a “no gain, no loss” basis, assets can be transferred without triggering CGT, then sold by the recipient spouse using their exemption. This strategy can effectively double the tax-free amount available to a couple, from £3,000 to £6,000 per tax year. However, transfers must be genuine and not part of artificial arrangements designed solely to avoid tax.
Spouse B sells asset, uses their £3,000 exemption
Spouse A independently sells assets with £3,000 gain, uses their exemption
Total tax-free gains: £6,000
Reporting and Payment Deadlines
The timing of CGT reporting and payment depends on the type of asset disposed of. For UK residential property disposals by UK residents where CGT is due, you must report and pay within 60 days of completion using HMRC’s Capital Gains Tax on UK property service. This applies even if you file Self Assessment returns annually. Failure to report within 60 days triggers automatic penalties and interest on late payment. The 60-day deadline runs from the date of completion, not the date of exchange or the date you receive funds.
For all other disposals (shares, non-residential property, overseas assets, etc.), UK residents report gains through their annual Self Assessment tax return with the CGT due by 31 January following the tax year end. Non-residents disposing of UK property must also report within 60 days, regardless of the property type. Keeping accurate records of all disposals throughout the year is essential for completing your return correctly and avoiding enquiries from HMRC.
Scottish Tax Considerations
While Scotland has its own income tax rates that differ from the rest of the UK, Capital Gains Tax rates are set at the UK level and apply uniformly across England, Wales, Scotland, and Northern Ireland. However, Scottish taxpayers face a complication when determining their CGT rate: the Scottish income tax bands differ from the rest of the UK, with a starter rate of 19%, basic rate of 20%, intermediate rate of 21%, higher rate of 42%, and additional rate of 48%. When calculating whether gains fall within basic or higher rate for CGT purposes, UK tax bands (20%, 40%, 45%) are used, not the Scottish bands.
This means Scottish taxpayers may find themselves paying income tax at the Scottish higher rate of 42% on income, but CGT at only 18% on gains that fall within the UK basic rate band. The interaction between the two systems can create planning opportunities and complexities that Scottish taxpayers should discuss with their tax advisers.
Non-Residents and UK Property
Non-UK residents are subject to Capital Gains Tax on disposals of UK residential and commercial property, as well as on disposals of interests in “property-rich” companies where the value derives primarily from UK property. The rate of CGT for non-residents is 18% for basic rate equivalent gains and 24% for higher rate equivalent, the same as for UK residents. Non-residents must report all UK property disposals within 60 days of completion, whether or not there is a gain, and pay any CGT due at the same time.
The rules for non-residents can be particularly complex, especially concerning the interaction with any available double taxation treaty between the UK and the country of residence. Private Residence Relief is available to non-residents only if they meet certain conditions regarding overnight stays in the UK property (at least 90 nights in a tax year) or they are tax resident in the country where the property is located. Professional advice is strongly recommended for non-residents with UK property interests.
If you become non-UK resident for fewer than five complete tax years and dispose of assets while abroad, those gains may be taxable when you return to the UK. These anti-avoidance rules prevent individuals from becoming temporarily non-resident simply to avoid CGT on planned disposals.
Investors Relief
Investors Relief offers a reduced CGT rate on gains from qualifying shares in unlisted trading companies. Like Business Asset Disposal Relief, the rate is 14% from April 2025, rising to 18% from April 2026. However, Investors Relief has a much higher lifetime limit of £10 million compared to BADR’s £1 million limit. The relief is designed to encourage investment in smaller companies by providing a lower tax rate on successful exits.
To qualify, shares must be newly issued ordinary shares in an unlisted trading company, subscribed for in cash, and held for at least three years before disposal. Unlike BADR, the investor does not need to be an employee or officer of the company. This makes Investors Relief particularly attractive for angel investors and those backing early-stage businesses without taking an active role. The interaction between Investors Relief and other reliefs can be complex, and professional advice is recommended when planning exits from qualifying investments.
Gift Hold-Over Relief
When you give away an asset that has increased in value, you normally trigger a CGT disposal at market value, even though you have not received any cash. Gift Hold-Over Relief allows the gain to be “held over” and deferred until the recipient disposes of the asset, effectively transferring your gain to the recipient. This relief is available on gifts of business assets and gifts to certain trusts, but not on gifts of personal assets like investment properties or share portfolios in quoted companies.
Where Gift Hold-Over Relief applies, both donor and recipient must make a joint claim. The effect is that the recipient takes over the asset at the donor’s base cost rather than market value, meaning any gain is preserved until eventual disposal. This can be useful for passing business assets to the next generation without triggering immediate CGT, although Inheritance Tax implications should also be considered. The interaction between CGT and IHT on gifts requires careful planning and usually professional advice.
Practical Tax Planning Strategies
Effective CGT planning combines multiple strategies to minimise tax over time. Using your annual exemption every year rather than letting it go to waste can save significant tax over a lifetime of investing. Transferring assets between spouses to utilise both exemptions doubles the available tax-free amount. Timing disposals to fall in years when your income is lower can reduce the CGT rate from 24% to 18%, potentially saving thousands in tax on a single disposal.
Investing through tax-advantaged accounts eliminates CGT entirely on growth within those wrappers. ISAs allow up to £20,000 per year of contributions to grow completely free of CGT and Income Tax. Pensions offer even greater benefits, with tax relief on contributions and CGT-free growth. For higher earners, Venture Capital Trusts (VCTs) and Enterprise Investment Scheme (EIS) investments offer CGT exemption on qualifying disposals after three years, alongside upfront income tax relief on investment. Understanding and utilising these allowances and reliefs is central to tax-efficient wealth building.
Common CGT Mistakes to Avoid
Many taxpayers make costly mistakes when dealing with Capital Gains Tax. Failing to report property disposals within 60 days results in automatic penalties and interest. Overlooking allowable costs reduces deductions and increases the tax bill unnecessarily. Not utilising the annual exemption wastes valuable tax-free disposal capacity. Ignoring the interaction with Income Tax can result in paying higher CGT rates than necessary. Assuming your main home is automatically exempt without checking the qualifying conditions can lead to unexpected tax bills.
Another common mistake is failing to keep adequate records of acquisition costs, improvement expenditure, and disposal proceeds. HMRC can enquire into CGT returns for up to four years from the end of the tax year (longer if careless or deliberate errors are suspected), so records should be retained for at least this period. For assets held for many years, tracking down original purchase documentation can be challenging, but making reasonable estimates where records are unavailable is better than claiming no deductions at all.
Frequently Asked Questions
Conclusion
Capital Gains Tax is a significant consideration for anyone disposing of assets that have appreciated in value. The 2025/26 tax year brings harmonised rates of 18% and 24% across all asset types, combined with a reduced annual exemption of just £3,000. Understanding how to calculate your gain, which reliefs might apply, and how to report and pay on time is essential for compliance and effective tax planning. Our calculator provides instant estimates based on your inputs, but professional advice is recommended for substantial or complex disposals.
Effective CGT planning can save significant amounts over a lifetime of investing. Using annual exemptions every year, transferring assets between spouses, timing disposals to minimise rates, and investing through tax-advantaged accounts all contribute to a tax-efficient approach. The key is to plan ahead rather than considering tax only at the point of disposal. With the right strategy and professional guidance where needed, you can ensure you pay the correct amount of tax while maximising legitimate reliefs and exemptions available under UK law.