Understanding Capital Gains Tax: Rates, Rules and Exemptions

Capital Gains Tax is a tax on the profit you make when you dispose of an asset that has risen in value. Disposal is wider than sale: it covers selling, giving away, swapping, and receiving compensation such as an insurance payout.

The OECD (2025) notes that gains are “typically taxed on a realisation basis”. An unrealised gain, a rise in value with no disposal yet, generally waits.

The UK list runs as follows.

Most OECD countries fully exempt the gain on a main residence. How a fund passes its own gains on to investors is a separate matter, and part of the question of whether ETFs are more tax-efficient.

One line per jurisdiction, as published by each jurisdiction's official sources and read in October 2026: nine that tax gains, then five with no general tax on gains, each group in alphabetical order.

A headline rate is not a bill. The holding period, an annual amount, your income and above all your residence and the asset's location change the result.

In the United States, an asset held more than one year gives a long-term gain; held one year or less, a short-term gain taxed at ordinary income rates.

That design is not universal. According to the OECD (2025), most OECD countries did not make the treatment of gains on listed shares depend on a holding period in 2023: 25 applied no differential treatment, among them Germany, Ireland, Italy, Japan, Spain and the United Kingdom. Germany's final withholding tax covers gains on securities “regardless of how long they are held”.

For 2026 to 2027 the UK annual exempt amount stands at £3,000, after £6,000 in 2023 to 2024 and £12,300 in 2022 to 2023 (HMRC, April 2026). The United States has no annual exempt amount and uses a 0% band instead.

Three amounts decide a gain: what the disposal brought in, what the asset cost, and the allowable costs of buying and selling, such as stockbrokers' fees and Stamp Duty Reserve Tax on a share purchase. Allowable losses are then deducted, and the total is compared with the annual amount.

Take one investor and one holding.

The tax is about 15% of the gain. A higher rate taxpayer would pay 24% on the same £14,400, or £3,456.

The gain goes in the Self Assessment return for 2026 to 2027, or through HMRC's real time service, which GOV.UK says must be used by 31 December in the tax year after the gain, with payment by 31 January.

This is an illustration on stated assumptions, not an official example; Scottish taxpayers are not covered.

Losses. A loss is deducted from the gains of the same tax year, and what is left can be carried forward. Most countries allow as much, the OECD notes, “typically with limitations”. The limits differ: in the United Kingdom, a claim up to 4 years after the disposal's tax year has ended; in the United States, a capped yearly deduction.

A rate means nothing until you know which country applies it. A country generally taxes its residents on their gains wherever they arise. Some countries also charge non-residents on certain assets, so a gain made in one country by a resident of another can be taxed twice.

Every line above depends on where you are tax resident in the year of the disposal. That status comes from each country's own rules, and two countries can both claim it. This guide does not decide it.

Where a tax treaty applies, it usually divides the right to tax: the UK-US convention lets the country of the property tax a gain on land and leaves most other gains to the seller's country of residence, one case of which country taxes a gain under a treaty.

Five lines of the table carry no general tax on an individual's gains, each with a limit of its own.

Zero at home is not zero everywhere. If you live in the UAE, the absence of tax in your State of residence says nothing about the State where the asset is: UK land stays taxable in the United Kingdom for a non-resident, and Spanish property is taxed in Spain. A person who returns to the United Kingdom within 5 years of leaving can also see certain gains brought back into charge.

A rise in value alone is generally not taxed. But a sale is not the only disposal.

Some countries also treat leaving as a disposal, Canada for instance when a person ceases to be resident; exit taxes on a change of country are treated separately.

Because countries do not agree on which events count, nor on the value an asset takes afterwards, a gift, an inheritance or a move that crosses a border can lead to double taxation of the same gain.

Four factors place a gain before any rate applies.

Reducing the bill. UK law contains allowances, a transfer rule between spouses and civil partners, and reliefs, each with conditions and limits, and a line beyond which HMRC speaks of avoidance. How to reduce capital gains tax is the subject of a separate guide.

Property. A property sale has rules of its own: a relief on the main home, a return and payment within 60 days for UK residential property, and a UK charge that follows the land even when the seller lives abroad. Capital gains tax on property has its own guide.

Spain. Spain taxes residents and non-residents under two different taxes, and a non-resident's property sale comes with an amount withheld by the buyer and a separate town hall tax. Capital gains tax in Spain has its own guide.

These four factors rarely stand alone, and how they combine depends on personal circumstances.

This guide is provided for general information purposes only and does not constitute tax, legal or financial advice. Rules and rates were read on official sources in October 2026 and may change; the worked example is an illustration. Outcomes depend on individual circumstances.