The average construction value per square meter that is taken into account in the IMI calculation will rise in 2026.
The Ministry of Finance increased the value of the square meter of construction that counts towards the IMI calculation. This means that whoever buys, inherits or revalues the house in 2026 will pay more tax from now on.
It is the highest value ever. The square meter of construction is defined by the Ministry of Finance and has not been updated since 2023. Next year, it will be 712.50 euros.
The price per square meter of construction is just one of the elements that make up the IMI calculation formula. In your property register you have all the elements: those that vary due to time are what has changed now, the value of the location and the age of the property.
Now let’s go to savings. If you have never submitted the IMI Model 1 to the Finance Department asking for a revaluation, it is likely that you are still paying IMI as if your house were new, debuting. The asset value is automatically updated by AT based on inflation, but always upwards, never downwards.
To download, each owner can ask the Finance Department – every 3 years – to redo the calculation. If you simulate and see that it drops, you will pay less IMI from the following year onwards.
The problem is that most Portuguese people don’t know how to calculate this. That’s why you should use simulators – which you can find online – to find out whether it’s worth asking for a reassessment or not. This warning is important because if you don’t do the math right, you could end up paying more IMI instead of going down.
Savings can range from a few euros to tens or hundreds of euros per year.
If you discover that you are paying too much IMI, request a review online at before December 31st.
If you do nothing, you will probably pay more EMI in the coming years.
