London · Guide · Selling a UK home from abroad

Selling a London home from Kuwait: HMRC requires every non-resident to report the sale within 60 days of completion, even when no tax is due, and taxes the gain on a home at 18% or 24%

A Kuwaiti who owns a flat in London owes no Capital Gains Tax while holding it, but the day it is sold, the UK rules on gains apply. HM Revenue & Customs (HMRC) says anyone who is not resident in the UK must report every disposal of UK property or land, even when there is no tax to pay or the sale makes a loss, and for a home that completes on or after 27 October 2021 the report and any tax are due within 60 days of completion. The gain is taxed at 18% or 24% for residential property, after a tax-free allowance of £3,000 for an individual. For a home owned before 6 April 2015, only the rise in value since 5 April 2015 is normally taxed. We opened HMRC's guidance, its 2026 helpsheet HS307 and the GOV.UK rates pages today.

Al Mithaq news desk · Published 27 October 2026 · Source: GOV.UK

Stucco and brick terraced homes with iron balconies on Thurloe Square, South Kensington, London, in summer daylight with a tree-lined street. Picture: No Swan So Fine, Wikimedia Commons, CC BY-SA 4.0

60 daysfrom completion to report the sale to HMRC and pay any tax, for UK homes completed on or after 27 October 2021

18% or 24%the Capital Gains Tax rates on a gain from residential property, depending on your taxable UK income

£3,000the tax-free allowance an individual deducts from the gain

Who must report, and when

HMRC's guidance says that if you are not resident in the UK you must report disposals of UK property or land even if you have no tax to pay, made a loss, or are already registered for Self Assessment. For a sale with a completion date on or after 27 October 2021 the deadline is 60 days after completion; for completions between 6 April 2020 and 26 October 2021 it was 30 days. The GOV.UK page on reporting and paying says the same 60 days apply to paying any tax, and that while UK residents report online only when their total gains are above the tax-free allowance, non-residents must report every sale or disposal. The report is made through an online Capital Gains Tax on UK property account or, if you cannot report online, by post on a Capital Gains Tax on UK property form; for a postal report, HMRC then sends a payment reference starting with 'x', which you need to pay any tax by the deadline. You will need the property's address and postcode, the dates you acquired it, exchanged contracts and completed, what it cost and what it sold for, the costs of buying, selling or improving it, any reliefs you claim, and, if you are not a UK resident, the type of property. If you do not report and pay on time, HMRC says you may have to pay interest and a penalty. The duty also covers indirect disposals: selling an interest of at least 25% in an entity that draws 75% or more of its gross value from UK land.

How much tax: the rates and the allowance

HMRC's 2026 helpsheet HS307 gives the Capital Gains Tax rates for disposals of interests in residential property in the 2025 to 2026 tax year as 18% and 24%. The GOV.UK rates page gives the same two rates for gains from 6 April 2026: 24% for higher and additional rate taxpayers, and for basic rate taxpayers 18% on the part of the gain that keeps their combined taxable income and gains within the basic rate band and 24% on any amount above it. HMRC's calculation guidance tells a non-resident to add up their taxable UK income and use that figure to work out the rate. An individual deducts the tax-free allowance, the Annual Exempt Amount, which the GOV.UK allowances page gives as £3,000 for individuals and £1,500 for trusts. If the property was your residence, HMRC says Private Residence Relief may apply to all or part of the gain. If the seller already files a UK Self Assessment tax return, the sale must also go on it, unless the property was their main home and qualifies for Private Residence Relief. Since 6 April 2019, non-resident companies pay Corporation Tax, not Capital Gains Tax, on gains from UK property or land.

Owned before April 2015: normally only the rise since then

For a residential property owned before 6 April 2015, HMRC's standard approach is to use its market value at 5 April 2015 instead of the original price. With that method you deduct only improvement costs incurred from 5 April 2015, plus the incidental costs of selling. HMRC's guidance lists two alternatives: time apportionment, which works out the gain over the whole period of ownership and taxes the share that falls after 5 April 2015, and the gain over the whole period, which it says may only be worth considering if you made a loss. HMRC also says no valuation had to be made in April 2015: you can wait until you sell, though a record of the home's condition at the time helps. HS307 gives an example: a property bought in 2012 for £30,000, worth £50,000 at 5 April 2015 and sold for £100,000 with £1,000 of selling costs. Only the £50,000 value can be deducted from the net proceeds of £99,000, giving a gain of £49,000; £10,000 spent on improvements in 2013 cannot be deducted because it was spent before 5 April 2015.

Bought after April 2015: price, costs and improvements

For a home bought after 5 April 2015 there is no rebasing: the gain is the sale price less what the home cost. HMRC's guidance deducts the acquisition cost, the incidental costs of acquisition and enhancement costs, meaning money spent improving the property, together with the incidental costs of selling; HMRC's Capital Gains Manual (CG15250) defines incidental costs as the fees of surveyors, valuers, agents and legal advisers, costs of transfer or conveyance including stamp duty land tax, and advertising costs. Keep the completion statements from both the purchase and the sale, the invoices for improvements and the agent's and solicitor's bills, because HMRC asks for the costs of buying, selling or improving the property when you report. Our 19 October guide covers the other side of owning a London home from Kuwait, the tax on the rent while you hold it.

Why it mattersOur view for a Kuwaiti owner: the 60 days start at completion, not at the end of the tax year, so plan the report before you sign the sale. Keep the papers that lower the gain from the day you buy: the completion statement, the stamp duty and legal bills, and the invoices for any improvement such as a new kitchen or an extension. A worked example (our own calculation, for a home bought after April 2015): you bought a London flat for £650,000 and paid £20,000 in stamp duty and legal costs, and you sell it for £760,000 with £10,000 of agent and legal costs. The gain is £80,000; after the £3,000 allowance, £77,000 is taxable. If you have no other taxable UK income, the first £37,700 of it (the 2026 to 2027 basic rate band on the GOV.UK rates page) is taxed at 18% and the other £39,300 at 24%, so the tax is £16,218; any taxable UK income, including UK rent, uses up the 18% band first and pushes the tax up towards £18,480, the figure at 24% on the whole £77,000. If the flat sold at a loss, you still report it within 60 days. If you own through a company, the rules are different again: it pays Corporation Tax, not Capital Gains Tax. HMRC's pages do not replace advice for your own case; speak to a UK tax adviser before you sell.

What Al Mithaq adds

Our London guide explains who can buy, the steps from reservation to keys, stamp duty with a worked example, and the London Square and Arada developments we offer. Read also our guides to stamp duty for overseas buyers and to the tax on London rent, and our report on London house prices in August. We do not give tax advice: for your own tax position, speak to a UK tax adviser before you sell. Tell our team in Kuwait your budget and whether you plan to live in the home or let it, and we will answer on the developments, prices and buying steps by call or WhatsApp on the same working day.

Sources

Key facts

Who: Anyone not resident in the UK who sells or disposes of UK property or land, even with no tax due or a loss (HMRC)
Deadline: Report and pay within 60 days of completion (completions on or after 27 October 2021)
How: Online Capital Gains Tax on UK property account; by post on HMRC's form only if you cannot report online (payment reference starting with 'x')
Rates, residential: 18% and 24%, depending on taxable UK income (HS307 2025 to 2026; GOV.UK rates from 6 April 2026)
Tax-free allowance: £3,000 for individuals, £1,500 for trusts
Owned before 6 April 2015: Standard method: market value at 5 April 2015; alternatives: time apportionment or whole-period gain
Also: If you already file Self Assessment, the sale goes on that return too, unless it was your main home and qualifies for Private Residence Relief
Companies: Non-resident companies pay Corporation Tax on UK property gains since 6 April 2019
Late: Interest and a penalty may apply
Worked example: Bought £650,000 + £20,000 costs, sold £760,000 less £10,000 costs: gain £80,000, taxable £77,000, tax £16,218 with no other UK income, up to £18,480 (our calculation)