Why the distinction became decisive
Levelling the rates removed the differentiation by type of work and replaced it with a differentiation by use of the property. The use of the property has therefore become the decisive variable.
For the 2026 tax year the rate is 50 per cent for works on the unit used as the claimant's main home and 36 per cent for works on any other unit. Neither rate depends on the type of operation.
The gap is fourteen points. On works at the renovation deduction cap the difference in total benefit exceeds thirteen thousand euros. It is not a classification detail: it is the variable weighing most on the financial plan of a residential project.
The tax meaning
The term has its own meaning in tax law, coinciding neither with everyday usage nor with registered residence alone. Habitual residence is the substantive condition.
In tax law the main home is the property unit in which the taxpayer or their family members habitually reside. Habitual residence is the substantive condition, and registration is its ordinary but not exclusive means of proof.
Two practical consequences.
The first is that the check belongs to the taxpayer's sphere and not to the professional's. A professional is not required to establish where a client habitually resides, but is required to ask the question and to state the assumption on which the estimate rests.
The second is that the classification refers to the person claiming the deduction. A property that is the main home of someone other than the person incurring the expenditure does not give the latter the enhanced rate, save in the situations where the rules allow cohabiting family members to claim.
When the classification is assessed
This is the aspect on which practice has had to intervene and where uncertainty remains. It concerns the moment at which use must be verified.
The deduction follows the expenditure incurred in each tax year, and the classification of the unit must be assessed against the position the rules treat as relevant. The relevant point in time should be checked against current practice.
Two recurring situations follow that are worth isolating. They concern losing and acquiring the status during the works.
A property that is the main home when the works begin and ceases to be so during the works raises a question of continuity of the condition. The question should be put to the tax adviser before the return is filed.
A property that becomes the main home only once the works are complete, an extremely common situation because people renovate in order to move in, raises the opposite question. The move of habitual residence is worth documenting as soon as it happens.
In both cases the actual outcome depends on the revenue administration's practice, which has given guidance on situations of this kind. It is the point on which the client should be directed to their tax adviser before the estimate is formalised.
| Situation | Applicable rate |
|---|---|
| Unit used as the claimant's main home | 50 per cent |
| Any other property unit | 36 per cent |
| Appurtenance of the main home | Follows the principal property, relationship to be documented |
| Common parts, owner whose unit is a main home | 50 per cent on their share |
| Common parts, owner whose unit is not | 36 per cent on their share |
Appurtenances
Appurtenances of the main home ordinarily follow the classification of the principal property. The appurtenance relationship must be documented.
The practical consequence concerns works on cellars, garages and ancillary rooms: whether they attach to the main home must be checked on the basis of the appurtenance relationship rather than their separate land registry classification. Land registry classification alone is not decisive.
One element deserves noting for completeness: in determining the cap on deductions applying to higher incomes, total income is taken net of the income of the unit used as the main home and its appurtenances. It is a rule operating on a different plane but confirming the systemic weight of the concept.
Works on common parts
In buildings under common ownership the rule produces an effect that should be explained to the general meeting before works begin. The net benefit differs from one owner to another.
The expenditure is incurred by the owners' association but the deduction belongs to each individual owner, and the rate is determined owner by owner according to the use of their unit. The determination is made unit by unit.
In the same building, for the same works on common parts, some owners will apply 50 per cent and others 36 per cent. The difference should be anticipated at the meeting rather than discovered at return stage.
The consequence for the professional advising the association concerns communication: the estimate presented to the general meeting cannot state a single net benefit, because that benefit differs for each owner. What should be presented is the expenditure, the ownership share and the mechanism, not the individual outcome.
The implications for estimating
Three operational points close the picture. They concern the check, the unit by unit calculation and the communication.
Information on the use of the property should be obtained at the start of the appointment, together with the land registry data and the title. It is a question that takes two minutes and whose omission produces an indeterminate estimate.
The assumption should be stated in the estimate. Writing that the calculation treats the unit as the client's main home protects the professional and makes clear to the client what the figure rests on.
On works covering several units with different uses, the calculation must be made unit by unit rather than in aggregate, because the rate differs. An aggregate figure is one no single unit achieves.
The most frequent errors
Applying the enhanced rate out of habit is the first, and is today the costliest estimating error. The check costs minutes and belongs before the estimate.
Confusing registered residence with habitual residence is the second, and overlooks that the latter is the substantive condition. The registration is an indication and not exclusive proof.
Presenting a single net benefit to a general meeting is the third, and produces complaints from the owners who receive the lower rate. The presentation should be built by bands of use.
Treating appurtenances as separate units is the fourth. The appurtenance relationship determines the classification.
Note: the information in this page relates to Italy and refers to the tax year stated. The tax meaning of main home and its application to transitional situations are clarified by the revenue administration's practice: the text in force should be checked before any operational use.