What is the UK capital gains annual exempt amount for the 2026 to 2027 tax year?

The annual exempt amount is 3,000 pounds for individuals, according to HMRC's guidance at gov.uk/capital-gains-tax/allowances. It is the amount of net chargeable gains a person can realise in a UK tax year, running 6 April to 5 April, before Capital Gains Tax is due. Each spouse or civil partner has their own, and an unused amount cannot be carried forward.

Does the IRS recognise the UK capital gains exempt amount?

No. The US has no equivalent relief. A US citizen living in the UK reports every disposal on Form 8949 and Schedule D, computed in dollars, and pays US tax on the net gain at short-term or long-term rates. A gain sheltered by the UK exempt amount bears no UK tax, so it produces no foreign tax credit of its own.

Do I have to report a gain to HMRC if it is below the exempt amount?

Sometimes. HMRC's guidance says a person registered for Self Assessment must report gains within the allowance if the total amount the assets were sold for exceeded 50,000 pounds, a threshold applying from the 2023 to 2024 tax year onwards. Investors who rebalance sizeable portfolios usually exceed that level of proceeds, so the capital gains pages are completed even when no UK tax is due.

Can I claim a foreign tax credit for UK capital gains tax paid after my US return is filed?

Yes, but the year matters. IRS Publication 514 allows the credit in the year the foreign tax is paid or, by election, the year it accrues, with a one-year carryback and ten-year carryover of unused tax. UK tax on a gain realised after 5 April is typically paid in the second following January, so the paid basis can miss the US year of the gain.

Can a UK capital loss be a taxable gain on my US return?

Yes. The US gain is computed in dollars, translating the purchase cost at the purchase-date exchange rate and the proceeds at the sale-date rate. If sterling strengthened against the dollar over the holding period, a sterling loss can become a dollar gain. No UK tax arises on the disposal, so there is no foreign tax to credit against the US tax.

Does transferring shares to my spouse to use two UK exempt amounts work for US tax?

It works for UK tax: HMRC confirms transfers between spouses living together are free of Capital Gains Tax and the original cost carries over. For US income tax, section 1041 gives non-recognition between spouses, but section 1041(d) switches that rule off where the receiving spouse is a nonresident alien, so the transfer needs a US analysis before it is made.

US UK Tax Returns Preparation: UK CGT Exempt Amount

US UK tax returns preparation for an American investor living in Britain has to start from one awkward fact: the UK capital gains annual exempt amount is a UK relief only, and the US return gives it no weight at all. For the 2026 to 2027 UK tax year the exempt amount is 3,000 pounds, and the slice of gain it shelters carries no UK tax, so it generates no foreign tax to credit against the US tax on the same gain. In the returns we prepare, that slice is rarely the largest number on the page, but it is the one investors least expect to be taxed, and it sits on top of deeper differences in how the two countries measure a gain in the first place.

This guide is written for US citizens and green card holders who are UK resident and hold a sizeable taxable portfolio of listed shares and funds in their own names.

What is the UK capital gains annual exempt amount for 2026 to 2027?

The annual exempt amount is the amount of net chargeable gains an individual can realise in a UK tax year before any Capital Gains Tax is due. HMRC's guidance at https://www.gov.uk/capital-gains-tax/allowances gives the current figure as 3,000 pounds for individuals. It was reduced to that level from April 2024, and an unused exempt amount cannot be carried into a later year.

Three features matter for a cross-border investor. The exempt amount is per person, so spouses and civil partners each have one. It is measured against UK-computed gains in sterling for the UK tax year running from 6 April to 5 April, which is neither the currency nor the period of the US return. And it is applied to net gains after current-year losses.

What does the UK charge above the exempt amount, and when must a gain be reported?

Above the exempt amount, HMRC's rates page at https://www.gov.uk/capital-gains-tax/rates shows that for gains made from 6 April 2026 an individual pays 18 per cent to the extent the gain falls within the unused basic rate band and 24 per cent above it. The rates on shares were raised to these levels for disposals on or after 30 October 2024, which aligned them with the residential property rates.

Reporting is a separate question from paying. HMRC's guidance at https://www.gov.uk/capital-gains-tax/work-out-need-to-pay says tax is due when total taxable gains exceed the allowance, but a person who is registered for Self Assessment must still report gains that are within the allowance where the total amount the assets were sold for was more than 50,000 pounds, a threshold that applies for the 2023 to 2024 tax year onwards. An investor who rebalances a large portfolio passes 50,000 pounds of proceeds quickly, so the capital gains pages are completed every year whether or not UK tax is due.

UK residential property has its own timetable: any Capital Gains Tax due must be reported and paid within 60 days of completing the sale, and the guidance at https://www.gov.uk/report-and-pay-your-capital-gains-tax adds that other gains reported through the real time service must be reported by 31 December in the tax year after the gain and paid by 31 January, the same date on which a Self Assessment filer settles the year.

Why does US UK tax returns preparation treat the exempt slice as fully taxable?

The US has no annual exempt amount for capital gains. A US citizen is taxed on worldwide income wherever they live, and every sale of a capital asset is reported on Form 8949 and summarised on Schedule D of Form 1040, and IRS Topic 409 at https://www.irs.gov/taxtopics/tc409 sets out the rules. A disposal that produced a 2,900 pound gain and no UK tax is still a line on Form 8949.

The US rate depends on the holding period. Topic 409 states that an asset held for more than one year before disposal produces a long-term gain or loss, and an asset held for one year or less produces a short-term one. Net long-term gains are taxed at 0, 15 or 20 per cent depending on taxable income; for the 2025 tax year the IRS shows the 20 per cent rate applying above 533,400 dollars of taxable income for a single filer and 600,050 dollars for a married couple filing jointly, with the thresholds adjusted each year. Net short-term gains are taxed at ordinary income rates. The UK draws no holding-period distinction, so a position sold after eleven months is taxed at 24 per cent in the UK and at the investor's top ordinary rate in the US.

On top of income tax sits the net investment income tax. IRS Topic 559 at https://www.irs.gov/taxtopics/tc559 describes it as a 3.8 per cent tax on the lesser of net investment income or the excess of modified adjusted gross income over 250,000 dollars for a married couple filing jointly, 125,000 dollars for married filing separately and 200,000 dollars for a single filer, and it confirms that net gains from disposing of stocks, bonds and funds are included. The foreign tax credit provisions of the Internal Revenue Code operate against regular income tax rather than this additional tax, and whether the treaty supplies a credit against it has been contested in the US courts, so we treat the 3.8 per cent as a likely real cost and record the position taken on each return.

How much US tax falls on the UK-exempt slice? A labelled illustration

The following is an illustration only. The figures are assumed, the exchange rate of 1.30 dollars to the pound is an assumption applied to every date for simplicity, the investor is assumed to be a UK higher rate taxpayer in the 20 per cent US long-term bracket and above the net investment income tax threshold, and the dollar gain is assumed to equal the sterling gain translated at that single rate.

Small year. The investor realises a net long-term gain of 3,000 pounds in 2026 to 2027. UK tax: nil, because the gain is covered by the exempt amount. US gain: 3,900 dollars. US income tax at 20 per cent: 780 dollars. Net investment income tax at 3.8 per cent: 148.20 dollars. Foreign tax available to credit from this gain: nil. Total US cost of a gain the UK regards as tax free: 928.20 dollars.
Larger year. The investor realises a net long-term gain of 43,000 pounds. UK taxable gain: 40,000 pounds. UK tax at 24 per cent: 9,600 pounds, or 12,480 dollars. US gain: 55,900 dollars. US income tax at 20 per cent: 11,180 dollars. The exempt slice is still 3,900 dollars and the US tax attributable to it is still 780 dollars, but the UK tax on the other 40,000 pounds exceeds the US income tax on the whole gain.
Break-even. On these assumptions UK tax at 24 per cent on the gain above 3,000 pounds equals US income tax at 20 per cent on the whole gain when the gain is 18,000 pounds: 24 per cent of 15,000 pounds and 20 per cent of 18,000 pounds are both 3,600 pounds. If the US rate were 15 per cent the break-even gain would be 8,000 pounds.

The exempt slice is a real US cost in two situations: years in which total gains are modest, and years in which the gains that did bear UK tax cannot be matched to the US year or the US credit category. In a large-gain year taxed at 24 per cent, the four-point margin between the UK rate and the top US long-term rate can absorb the exempt slice within the credit limitation, because the limitation is computed on a category of income and not gain by gain. That only works if the credit arrives in the right US year and category, and the 3.8 per cent tax remains on top in every case.

Why can a sterling loss be a dollar gain?

The US return is computed in dollars. The IRS states at https://www.irs.gov/individuals/international-taxpayers/foreign-currency-and-currency-exchange-rates that amounts reported on a US return must be expressed in US dollars and that the exchange rate to use is the one prevailing when the item is received, paid or accrued. For a share sale that means the purchase cost is translated at the rate on the purchase date and the proceeds at the rate on the sale date. The UK computation uses sterling throughout, so the two results can differ in size and in sign.

A second illustration, again with assumed figures. An investor buys UK-listed shares for 100,000 pounds when the assumed rate is 1.20 dollars to the pound, giving a US cost basis of 120,000 dollars. The shares are sold for 95,000 pounds when the assumed rate is 1.35, giving US proceeds of 128,250 dollars. The UK result is a loss of 5,000 pounds. The US result is a gain of 8,250 dollars. There is no UK tax on the disposal, so there is nothing to credit, and the UK loss goes on to reduce UK tax, and therefore creditable tax, on another gain.

The reverse happens when sterling weakens over the holding period: a UK gain taxed at 24 per cent can be a smaller dollar gain or a dollar loss, leaving UK tax paid on income the US does not recognise. None of this can be seen from a UK broker's consolidated tax certificate, which is why we rebuild the dollar history of each lot instead of converting the sterling totals at a year-end or average rate.

How do UK share pooling and US lot identification change the gain?

The exempt amount is small beside the difference that the two matching systems can produce. HMRC helpsheet HS284, published at https://www.gov.uk/government/publications/shares-and-capital-gains-tax-hs284-self-assessment-helpsheet, sets out the UK order. A disposal is matched first against shares acquired on the same day, then against shares acquired in the 30 days following the disposal, known as the bed and breakfasting rule, and only then against the Section 104 holding, in which all shares of the same class in the same company are pooled and each share is treated as acquired at the same average cost.

The US does not pool ordinary shares. IRS Publication 550 at https://www.irs.gov/publications/p550 explains that where the investor can adequately identify the shares sold, the basis is the cost of those particular shares, and where they cannot, the earliest acquired shares are treated as sold first. The same sale out of a holding built over ten years is therefore measured against an average sterling cost in the UK and against specific dollar lots in the US. The mechanics are covered in a separate article; the point here is that the UK gain to which the 3,000 pound exempt amount is applied and the US gain on Form 8949 are different numbers before currency is even considered.

Where do loss harvesting and bed and breakfasting rules pull apart?

Many UK investors use the exempt amount deliberately each year by selling enough to realise around 3,000 pounds of gain. For a US citizen that habit manufactures a US-taxable gain with no UK tax attached, which is the exact slice illustrated above.

The anti-avoidance rules are also built differently, and the mismatches run in both directions:

The UK 30-day rule matches a disposal with a reacquisition in the following 30 days and applies to gains as well as losses, so selling and rebuying within the window does not crystallise the pooled gain or loss the investor intended.
The US wash sale rule, described in Publication 550, disallows a loss where substantially identical stock or securities are bought within 30 days before or after the sale. It looks backwards as well as forwards and it applies to losses only, so a gain realised and immediately repurchased is fully recognised in the US.
US net capital losses can offset only 3,000 dollars of other income a year, 1,500 dollars if married filing separately, with the rest carried forward, according to Topic 409. UK capital losses are not set against income in the ordinary case and are carried forward against future gains.

A year-end tidy-up designed around one country's rules often produces an unplanned result in the other, so we model both computations for the same proposed trades before the end of whichever tax year closes first.

When is UK capital gains tax creditable on the US return?

The two tax years do not match. The US year is the calendar year; the UK year ends on 5 April. A gain realised in May 2026 belongs to the 2026 US return and to the UK tax year 2026 to 2027, and the UK tax on it is ordinarily paid by 31 January 2028.

IRS Publication 514 at https://www.irs.gov/publications/p514 explains the two ways to bridge it. A cash method taxpayer can claim the credit only in the year the foreign tax is paid, but can choose to take the credit in the year the tax accrues, and foreign taxes generally accrue on the last day of the foreign tax year. The same publication allows unused foreign tax a one-year carryback and then a ten-year carryover, worked out separately for each category of income.

Apply that to the May 2026 gain. On the paid basis, UK tax paid in January 2028 is a 2028 credit; a one-year carryback reaches 2027 but not 2026, so the 2026 US tax on the gain is not relieved by it. On the accrued basis, the UK tax accrues on 5 April 2027 and is a 2027 credit, which can be carried back one year to 2026 by amending that return. This is one reason long-term UK residents with investment gains often use the accrued basis, though the choice binds later years and changes how the foreign tax is translated into dollars, so it should be made deliberately.

Which foreign tax credit category applies, and what is the capital gain rate adjustment?

Form 1116 is completed separately for each category of income. The instructions at https://www.irs.gov/instructions/i1116 put portfolio gains in the passive category in most cases, but passive income excludes high-taxed income, defined as income on which the foreign taxes paid, after allocation of expenses, exceed the highest US tax that can be imposed on it. With the UK charging 24 per cent and the top US long-term rate at 20 per cent, UK-taxed gains can meet that definition and move to the general category. The test is applied under grouping rules in the regulations and not simply asset by asset, so the category must be tested each year and never assumed.

The second complication is the capital gain rate differential. Because long-term gains are taxed at lower US rates than ordinary income, the Form 1116 instructions require most Schedule D filers to adjust foreign source capital gains before entering them in the limitation calculation, using Worksheet A or Worksheet B in the instructions or the fuller method in Publication 514. Broadly, gains taxed at the 15 or 20 per cent rates are scaled down so that the limitation reflects the US tax actually charged on them. There is an adjustment exception for smaller amounts of foreign source gains and dividends, but investors at the wealth level this article addresses rarely qualify for it. Skipping the adjustment overstates the credit, an error we often find when reviewing prior-year returns.

Source is the third point, and it bears directly on the exempt slice. Publication 514 states that a US citizen with a foreign tax home is treated as a nonresident for the sale of personal property, which is what makes the gain foreign source, only if an income tax of at least 10 per cent of the gain is paid to a foreign country. A gain wholly covered by the exempt amount bears no UK tax, so under the domestic rule it can remain US source and add nothing to the limitation. The treaty contains its own sourcing provision for US citizens resident in the UK, which carries separate Form 1116 consequences, and the interaction needs to be worked through on the facts.

Does the US-UK treaty stop the US taxing the gain?

No. Article 13 of the US-UK income tax convention, published by the US Treasury at https://home.treasury.gov/system/files/131/Treaty-UK-7-24-2001.pdf, allows gains on real property to be taxed where the property is situated and provides in paragraph 5 that gains on other property are taxable only in the state where the seller is resident.

The saving clause in Article 1, paragraph 4, removes that protection for Americans: the US may tax its citizens as if the convention had not come into effect, subject to listed exceptions. Article 13 is not among the exceptions, but Article 24 on relief from double taxation is, so the treaty's contribution for a US citizen in the UK is the credit mechanism and its sourcing rule and not an exemption.

Can transfers between spouses double the exempt amount?

Within the UK system, yes. HMRC confirms at https://www.gov.uk/capital-gains-tax/gifts that no Capital Gains Tax is paid on assets given or sold to a husband, wife or civil partner, unless the couple separated and did not live together at all in that tax year or the assets were goods given for the recipient's business to sell on. The recipient's gain on a later disposal is calculated by reference to when the transferor first owned the asset, so the original cost carries across. Moving shares to a spouse before a sale lets a couple use two exempt amounts.

The US position depends on the spouse's status. Where both spouses are US citizens, section 1041 of the Internal Revenue Code provides that no gain or loss is recognised on a transfer of property between spouses, and the transfer changes nothing on a joint US return: the gain is still on Form 8949 whoever sells. Where the receiving spouse is a nonresident alien, section 1041(d) states that the non-recognition rule does not apply. The income tax result of the transfer then turns on its terms; a transfer for payment, or one that settles an obligation, is treated as a disposal at that point on the US return.

A transfer to a non-US spouse therefore needs a US income tax analysis before it is made, alongside the other US rules on transfers between spouses, which this article does not cover. An election to treat the spouse as a US resident for filing purposes also changes the outcome, because it brings the spouse's later gains onto the US return.

What should a US citizen investor in the UK do before each tax year end?

One further trap deserves a sentence. A UK or other non-US fund, including a UK-listed investment company or an exchange-traded fund domiciled outside the US, is commonly a passive foreign investment company under the tests in the Form 8621 instructions at https://www.irs.gov/instructions/i8621, and gains on such holdings are taxed under a separate and harsher US regime that the 20 per cent long-term rate and the analysis above do not describe.

For directly held shares, the working checklist we use in preparation is short:

Compute every disposal twice: in sterling under the same-day, 30-day and Section 104 rules, and in dollars lot by lot at purchase-date and sale-date exchange rates.
Identify the gains that bear no UK tax, whether because of the exempt amount, UK losses or a sterling loss, and price the US income tax and the 3.8 per cent tax on them.
Map each UK tax payment to a US year on the paid or accrued basis, and check whether the one-year carryback actually reaches the year of the gain.
Test the Form 1116 category each year, apply the capital gain rate differential adjustment, and track carryovers by category.
Check proposed loss sales against both the UK 30-day rule and the US wash sale rule, including purchases by a spouse.
Check whether UK reporting is required even with no tax due because proceeds exceeded 50,000 pounds, and diarise the 60-day deadline for any UK residential property sale.
Analyse any transfer between spouses under both systems before it happens, particularly where one spouse is not a US person.

For a US citizen the annual exempt amount is 3,000 pounds of UK-free gain, not 3,000 pounds of tax-free gain. Treating the two as the same is the failure mode we see most often in portfolios arranged with only the UK return in mind.