If you are UK resident when you sell, an overseas property is within the UK CGT net. The detail that catches people out: the gain is computed in sterling, so the currency can create a taxable gain on its own.
If you are UK resident when you sell, you are within the scope of UK capital gains tax on the disposal of an overseas property, in the same way as on a UK one. The property being abroad, the sale being conducted abroad and the proceeds staying abroad make no difference to that.
This is the single most important thing on this page, and it surprises almost everyone. The gain is computed in sterling. Your acquisition cost is converted at the exchange rate on the date you acquired the property, and your disposal proceeds at the rate on the date you sold. The consequence is that you can have a taxable gain in sterling even if the property sold for exactly what you paid for it in the local currency — because the currency moved in between.
The reverse is also true, and equally worth knowing: a property that rose in baht terms can produce a smaller sterling gain, or a loss, if sterling strengthened. Either way, the currency movement is part of the taxable computation rather than a separate matter. This is a good reason to record the sterling acquisition value at the time of purchase, while you still have the rate.
Rates for residential property gains differ from those for other assets and have changed more than once in recent years, so check the current rate on the HMRC page below rather than relying on a figure quoted in an article.
The 60-day reporting-and-payment regime that applies to UK residential property disposals does not extend to overseas property. A gain on a property abroad is normally reported through Self Assessment for the relevant tax year, with tax due on the usual January deadline. That gives you more time, but it also means the liability can arrive a long time after the money did — set it aside at the point of sale.
Thailand applies its own charges on a property transfer, which are levied at the Land Office and are structured differently from a UK-style capital gains tax — see Thai capital gains tax on sale and selling a Phuket property later. Where the same gain is taxed in both countries, relief for the foreign tax paid is the mechanism that prevents a double charge; the interaction is not always straightforward, and it is worth taking advice before completing rather than after.
The position changes, and so does the planning. Temporary non-residence rules can pull a gain back into charge if you return to the UK within a certain period, so a plan built around a short spell of non-residence needs proper advice rather than a rule of thumb.
A note on figures. Rates, allowances and thresholds change at every Budget, and this page is written as at July 2026. We have deliberately kept specific numbers off it and linked to HMRC instead, so that you are reading the current figure rather than one we published months ago. The mechanics below are stable; the numbers are not. This is general information and not tax advice — take advice on your own circumstances before you act.
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See if you qualify →If you are UK resident at the time of disposal, yes - UK CGT applies to worldwide gains. It makes no difference that the property, the sale and the proceeds are all outside the UK.
In sterling. The acquisition cost is converted at the exchange rate on the acquisition date and the proceeds at the rate on the disposal date. That means a currency movement alone can create a taxable gain even if the local-currency price was unchanged - or reduce one if sterling strengthened.
No. The 60-day reporting and payment rule applies to UK residential property disposals, not overseas ones. An overseas gain is normally reported through Self Assessment for the relevant tax year, with tax due on the usual deadline.
Relief for foreign tax paid is the mechanism that prevents a genuine double charge, but the interaction between a foreign transfer-tax regime and UK CGT is not always straightforward. Take advice before completing the sale rather than afterwards.
Reviewed 2026-07-20 · Written by James Allwinton, who runs the research and the numbers behind every introduction at The Expat Investor. We are an introducer, not a financial, legal or tax adviser — this is general information, not advice.
How we source this: UK tax mechanics follow HMRC's published guidance on GOV.UK, linked inline on each page, and the UK–Thailand double taxation convention. Rates and thresholds change at each Budget, so we link to the live HMRC page rather than reprinting figures that go stale. This is general information, not tax advice — your own position depends on your residence, your other income and your holding structure. Figures for any specific building — price, service charge, sinking fund and the net yield actually achieved — are confirmed with you privately rather than published here.