Buy, renovate, sell

When a Portuguese property is sold, the price originally paid is normally uprated by a currency devaluation coefficient, which reduces the taxable gain and therefore the tax. It exists to compensate for inflation accumulated over the years of ownership.

The IRS Code makes that adjustment conditional on time: it applies only where more than 24 months have passed between acquisition and disposal. A buy-renovate-sell project almost always closes inside that window, and therefore gets no coefficient at all. The gain is taxed in full, with nothing softening it.

Since the property is not an own permanent home, there is no rollover relief either. Half the gain is aggregated with the rest of your income and taxed at the general progressive rates, which in a good year can push part of it into a higher band.

Costs that add value to the property are added to the acquisition value and reduce the gain, provided they were documented and carried out in the last 12 years. Documented is the word holding the sentence up: without an invoice in the seller's name, the work exists in the house but not in the tax return.

It is the decision with the most consequence in a project like this. Undocumented work is cheaper in the builder's quote and dearer in the gain, and the difference rarely pays. The same logic covers the IMT, stamp duty and deed costs paid on purchase: they are costs inherent to the acquisition, they add to the acquisition value, and the simulator already counts them.

There is an IMT exemption for buying to resell, but it is a regime for people in that trade: it requires a declaration of that activity filed before the purchase and proof, by certificate from the tax portal, of having carried it on in each of the two preceding years. Anyone doing a one-off project does not have it, and the simulator calculates without it.

Time. A project budgeted at eight months rarely closes at eight months, and every extra month is another month of holding costs, of interest if there is finance, and of exposure to a market that may have moved.

Permits. Depending on how far the intervention goes, it may need prior notice to the municipality or a full licence, and works do stop waiting for an opinion. Worth knowing which regime you are in before signing the purchase, not after.

And the sale price, which here is an expectation you typed in. It is the number that most influences the margin and the only one outside your control. Running the simulation with a cautious sale price, and seeing whether the operation still makes sense, is the most useful test this page allows.

If the result comes out negative, the page shows it and adds no advice. A project that does not close on the numbers is information, and finding that out beforehand is the point of doing the arithmetic first.

The tax figures in use are those in force in 2026 and are reviewed annually.