The building tax incentives currently available

The 2026 budget law extended for the whole year the regime already in force in 2025, with a distinction that governs the entire subject. The distinction concerns the use of the property unit.

Deduction	Main home	Other properties
Renovation deduction	50 per cent	36 per cent
Energy efficiency deduction	50 per cent	36 per cent
Seismic upgrade deduction	50 per cent	36 per cent
Furniture allowance	50 per cent	50 per cent

What determines the rate is therefore not the type of work but the use of the property being worked on. It is the systemic change of the last two tax years and the most frequent source of error in estimates presented to clients.

This point deserves isolating because a substantial share of the sources in circulation reports a superseded timetable. The timetable announced in earlier years has been changed more than once.

The 2025 budget law had scheduled a reduction in the rates from 2026. The 2026 budget law suspended that reduction, extending the more favourable conditions for the whole year and pushing the step down back by one year.

The result is that from 2027, subject to any further extension, the rates will fall to 36 per cent for the main home and 30 per cent in other cases. The reduction is already written into the rules and needs no fresh measure.

Anyone consulting a guide published in 2025 will therefore find rates given for 2026 that are no longer those applying. It is a check to make systematically before passing a figure to a client.

The Superbonus was not extended, and its closure is final. Only the remaining annual instalments of past expenditure survive.

What remains alive is only what follows from expenditure already incurred: the spreading of the remaining annual instalments, ongoing audits and litigation. The subject is covered in the branch devoted to audits.

Likewise, the accessibility incentive at 75 per cent stopped at expenditure incurred to the end of 2025. Works removing architectural barriers remain eligible, but within the renovation deduction and at its rates.

The renovation deduction is the reference measure, founded on the article of the income tax code governing the recovery of building stock. It covers the widest range of works and has a spending cap of 96,000 euros per property unit.

The energy efficiency deduction covers energy upgrading works and is distinguished by its caps, which are not single but differentiated by type of work, from whole building energy upgrading to the replacement of heating and cooling systems. Each cap must be checked against the actual type of work.

The seismic upgrade deduction covers seismic strengthening works and retains its own arrangements for spreading the relief compared with the other deductions. The spreading arrangements should be checked against the text in force.

The furniture allowance is not free standing: it is tied to a renovation project and allows the purchase of furniture and large appliances to be deducted within a spending cap of 5,000 euros. The link with the building works is a condition of access.

A technical limitation introduced recently bears directly on the design of building services works. It concerns boilers fuelled by fossil fuels.

Excluded from the energy efficiency and renovation deductions are works replacing winter heating systems with single boilers fuelled by fossil fuels, for expenditure incurred in the tax years the rules identify. The tax years concerned should be checked against the text in force.

The operational consequence is that a boiler replacement designed without checking this exclusion may turn out to be ineligible, with an effect on the financial plan of the project that the client discovers at tax return stage. The check should be made before the financial plan is set.

One recurring clarification deserves stating, because it confuses two planes that remain distinct. It concerns the relationship between the building consent and the deduction.

A tax relief does not replace the building consent and does not alter its regime. Eligible works remain subject to whatever consent the building rules assign to them, and works carried out without the required consent do not become regular because a deduction was claimed.

The relationship works the other way round: the documents evidencing the building regularity of the works form part of what must be retained for deduction purposes, and their absence is one of the elements a tax audit focuses on. Building regularity is therefore a documentary precondition of the deduction.

A working sequence follows that holds for every commission. Classify the works under the building rules and identify the consent. Check eligibility for the relief. Build the building application and the tax file in parallel. Reversing the first two steps leads to shaping a project around an expected tax benefit and then discovering that the consent required changes its scope.

Three points follow from the framework described. They concern the source, the use of the unit and the services exclusions.

The first concerns estimating. The applicable rate depends on the use of the property, and an estimate presented without having checked whether it is the client's main home is an indeterminate estimate.

The second concerns the calendar. A project spanning two tax years falls, for the expenditure incurred, under the rates of each year, and scheduling payments becomes an element of the financial design.

The third concerns sources. The rules change with every budget law and outdated guides remain indexed for a long time. The primary sources are the text of the year's budget law and the tax guide published by the revenue administration.