Usually, yes. The relief that protects a main home is the most valuable allowance in most property tax systems, and it generally does not travel to a second property. Once the home is also in another country, a second question arrives on top: which country taxes the gain, and does the other one tax it as well.
This guide covers the mechanics that decide the bill. It states no rate and no threshold, deliberately — those differ by jurisdiction, they change, and an out-of-date rate is the one thing in an article like this that a reader would actually act on.
The gain is not the price rise
The taxable gain is broadly the disposal proceeds minus your allowable costs, and "allowable costs" is a longer list than the purchase price alone.
Systems differ on what qualifies, but the categories commonly available include:
- The original purchase price
- Transfer tax, notary, legal and registry costs on acquisition
- Costs of sale, including agent commission and legal fees
- Capital improvements that enhanced the property, as distinct from repairs
That last distinction is the one that decides real money. A new kitchen replacing an old one may be a repair; an extension that did not exist before is usually an improvement. Repairs are generally not allowable against the gain, improvements generally are, and the line between them is drawn by the tax authority rather than by how much it cost you.
One further adjustment catches people who have let the property. Where a system has allowed depreciation or wear-and-tear relief against rental income, it commonly requires the base cost to be reduced by that relief on eventual sale — and in some systems by the relief you were entitled to claim whether or not you actually claimed it. If the place has ever been let, establish this before you model anything. The letting side is covered in our rental income tax guide.
Keep the invoices from day one
This is the single most valuable habit in this article, and it costs nothing.
Every claim you eventually make must be evidenced. Twenty years later, a decade of improvement work with no invoices is a deduction you cannot take, and the practical consequence is tax paid on money you actually spent. People routinely lose meaningful sums this way, not because they did not do the work but because they cannot prove it.
Open a folder on the day you complete. Put the completion statement in it, then every improvement invoice, every professional fee, and every relevant receipt as it happens. Keep it for as long as you own the property and for the retention period afterwards.
What the missing invoices actually cost
Invented numbers, used only for the arithmetic. No real rate or relief is implied.
Take a property bought for 400,000 and sold twenty years later for 700,000. The owner spent 90,000 on work over that period: an extension, a new roof, a rewire and a new kitchen.
With every invoice kept, and assuming the extension and the rewire qualify as improvements while the kitchen replacement and the roof repair do not, the allowable costs might be the 400,000 purchase, 20,000 of acquisition costs, 15,000 of selling costs, and say 55,000 of qualifying improvements. Total 490,000. Taxable gain: 210,000.
With no invoices, none of the 55,000 can be evidenced and none of it can be claimed. Allowable costs fall to 435,000. Taxable gain: 265,000.
The difference in the taxable gain is 55,000 — the exact amount of work that was genuinely done, genuinely paid for, and simply not provable. Whatever rate applies, the owner pays it on money they actually spent on the building. The work happened; only the paper was missing.
Two countries, one gain
On an overseas property the default position is that the country where the property sits taxes the gain, because that is where the asset is. Your country of residence may then tax the same gain as part of your worldwide income, and relief for the first tax against the second depends on the treaty between them.
That relief is rarely a clean cancellation. Treaties allocate taxing rights and then give credit, and a credit is capped at what your home country would have charged. If the property's country taxes at a higher effective rate than your own, the excess is generally not recoverable; if it taxes at a lower rate, you commonly top up to your home rate. Either way, the arithmetic is done on both returns and the timing rarely lines up. Our double taxation treaties guide sets out how the mechanism works.
There is a filing trap alongside it. Several countries require a disposal to be reported within weeks of completion, separately from and much sooner than the annual return, sometimes with the tax payable at the same time. Missing that is a penalty on a return you would have filed correctly anyway.
Currency turns a flat market into a taxable gain
On a cross-border sale the gain may be computed in the currency of the country doing the taxing, using the exchange rates at acquisition and at disposal.
Again, invented figures. Assume you are resident in one country and the property sits in another with a different currency.
You buy for 500,000 local units when the exchange rate is 1.00 to your home currency, so the purchase cost you 500,000 at home. Twenty years later you sell for exactly 500,000 local units — a completely flat market, no gain in local terms.
But the rate has moved to 1.20. The sale converts to 600,000 in your home currency. If your country of residence computes the gain in its own currency, you have a 100,000 gain and a bill on it, despite having received back precisely what you put in.
The reverse happens too, and can hand you a loss on a property whose local price rose. Neither outcome is avoidable. Both are foreseeable, and a cross-border disposal should be modelled in both currencies before it is agreed rather than after.
Note the second-order effect: a mortgage in the property's currency moves the other way, and in some systems the loan itself can produce a separate taxable gain when repaid. If the purchase was financed locally, ask about it specifically.
Timing and residence status frequently matter
Several systems apply relief that depends on how long you held the property, on how long it was your main residence, or on your residence status at the point of disposal.
Where such rules exist they can make the difference between a substantial bill and a small one, and they turn on dates. This is a case where a conversation with an adviser before you agree a sale is worth considerably more than the same conversation afterwards — after completion the dates are fixed and the planning options are gone.
Residence status is the sharpest edge here. Some systems tax a departing resident on unrealised gains, some tax a former resident who sells within a defined window after leaving, and some treat a non-resident seller differently on the same property. If a move and a sale are both in prospect, their order can matter more than their timing.
Inherited and gifted property has its own rules
If you did not buy the property, your acquisition cost is not obvious, and systems handle it differently — some substitute the market value at the date of death or gift, some carry over the original owner's cost, some tax the transfer itself at the time.
If you have inherited property or been given it, establish your base cost early rather than at the point of sale. The information needed — a probate valuation, the date, the original owner's records — is far easier to obtain near the event than years later, and it directly determines the eventual bill. The succession dimension is covered in inheritance tax on property abroad.
The mistakes that cost the most
| Mistake | What it costs | When to fix it |
|---|---|---|
| Discarding invoices | Tax on money you actually spent | From the day you complete |
| Confusing repairs with improvements | Deductions disallowed, or wrongly claimed | Before the work, ideally |
| Assuming main-residence relief carries over | An unbudgeted bill on the whole gain | Before you buy the second home |
| Ignoring past letting and depreciation | A base cost lower than you modelled | Before you model anything |
| Taking advice after agreeing the sale | Holding-period and residence reliefs lost | Two months before, not after |
| Missing a short post-completion filing deadline | Penalties on a correct return | At the point of sale |
| Not establishing the base cost of inherited property | Deduction you cannot evidence | Near the death or gift |
| Modelling in one currency only | A gain you did not know you had | Before agreeing the price |
What to ask your adviser
- Does main-residence relief apply to this property at all, and if not, has it ever?
- What exactly counts as an allowable improvement here, and what evidence will be required?
- Has any letting relief or depreciation reduced my base cost, whether or not I claimed it?
- Is there a holding-period relief, and what dates would I need to hit?
- Does my residence status at the point of disposal change the outcome, and would moving first help or hurt?
- In which currency is the gain computed, and using which exchange rates?
- Does my foreign-currency mortgage create a separate gain on repayment?
- Will the property's country and my country of residence both tax this, and how is relief given?
- If the property was inherited or gifted, what is my base cost and how is it evidenced?
- Are there reporting deadlines after completion that are shorter than the annual return?
The short version
Assume a second home carries tax on the gain. Keep every invoice from the first day. Model the sale in both currencies if it is cross-border. Check whether a short filing deadline applies after completion. Take advice before you agree the sale, not after.
The gain is calculated once and the arithmetic is unforgiving, but almost all of it is determined by paperwork you either kept or did not. The wider ownership cost picture sits in our property tax guide, and the structures people use to hold cross-border property in tax-efficient property ownership.
General information, not tax advice. Capital gains rules, reliefs, holding periods, filing deadlines and allowable costs differ by jurisdiction and change, so no rate or threshold is stated anywhere in this article. The worked examples use invented figures to show a mechanism and are not projections. Take professional advice in every relevant country before agreeing a disposal.
