Detailed calculation of IMU (property tax) and cadastral yield in Italy
- Florian Haaf
- 2 days ago
- 4 min read
The IMU (Imposta Municipale Propria) is the municipal property tax in Italy. It primarily affects holiday homes and second homes and is not calculated based on the purchase price or market value, but rather on the cadastral yield (rendita catastale) . The cadastral yield can be found on the cadastral extract (visura catastale), which is available online for every property.
For a typical residential property, the calculation can be represented as follows:
Cadastral tax × National factors × Municipal IMU rate = annual IMU
Essentially, three components determine the IMU level, which will be explained in more detail below.
1. Cadastral data
The cadastral value (rendita catastale) is a taxable value recorded for each property in the Italian land registry. For typical residential properties, it is calculated by multiplying the number of rooms (vani catastali) by the applicable cadastral tax rate (tariffa d'estimo) .
Number of rooms × cadastral rate = cadastral yield
Number of rooms
A cadastral room (vano catastale) is not simply a room in the German or Swiss sense. Rather, rooms are weighted differently according to their function.
Room type | Typical credit |
Living room, bedroom, study | 1 room |
Kitchen | Basically 1 room |
Bathroom, hallway, entrance | typically 1/3 room |
Basement, attic or similar ancillary rooms | typically 1/4 room |
The size of a room can also influence the rating. A particularly large main room may count as more than one room, while smaller bedrooms may only be counted as one-third.
Terraces, gardens, and similar areas are not counted as additional rooms. They can be accounted for by adding or subtracting them from the overall cadastral count. The final result is regularly rounded to the nearest half room. The defined number of rooms is shown in the cadastral extract under "vani".
The exact rules for how individual rooms are calculated and how surcharges and discounts are handled are defined via decades-old comparison schemes and are "hidden" in the archives of the respective province.
Room rate
The number of rooms (vani catastali) is then multiplied by the cadastral tariff (tariffa d'estimo) . The cadastral tariff is not the same throughout Italy , but varies depending on the municipality as well as the property's category and class.
The property category and class assigned to your property by the municipality can be found on the cadastral extract . It may state, for example: Category A/2 – Class 3.
The category generally describes the type of property. For example, A/2 designates a standard residential property, while A/3 typically represents simpler residential properties. The class further differentiates within the same category, taking into account the property's quality in more detail. The higher the property's category and class, the higher the cadastral tax rate.
The appropriate cadastral tariff can be researched using the municipality, category and class, for example via the following website:
For traditional residential properties, the cadastral tariff is multiplied by the previously determined number of cadastral rooms, as explained: Example 7 rooms × €175.59 cadastral tariff = approx. €1,229 cadastral income.
This cadastral data then forms the basis for the IMU.
2. National factors
For the calculation of the IMU, the cadastral yield is first increased by 5% by law :
Cadastral yield × 1.05
This value is then multiplied by a legally defined multiplier . For most residential properties in category A, as well as, for example, garages in category C/6, this multiplier is 160 .
These factors are derived from the national legal valuation rules for the IMU. They serve to derive a uniform tax base from the comparatively low cadastral yield.
For our example:
€1,229.17 × 1.05 × 160
Unlike the cadastral tariff and the subsequent IMU rate, these factors are not determined by the respective municipality , but apply nationwide to the corresponding property categories.
3. Municipal IMU rate
The IMU rate of the respective municipality is then applied to the result .
For typical holiday homes and second homes, the standard state rate is generally 0.86%. Municipalities can deviate from this and regularly increase the rate up to a maximum of 1.06% . The specific rate must therefore always be checked for the respective municipality and the relevant tax year .
4. Total Calculation
For an example holiday property, the calculation is as follows:
7 rooms × €175.59 cadastral tariff = €1,229.17 cadastral revenue
Afterward:
€1,229.17 × 1.05 × 160 × 0.95%
= €1,961.76 IMU per year
This makes it clear: The amount of the IMU is not primarily determined by the purchase price or living space, but by the cadastral yield (driven by the number of rooms and the classification of the property by the municipality) , national factors and the municipal IMU rate .
For garages, cellars or other ancillary units registered separately in the land register, there may also be a separate Rendita Catastale, which is included separately in the calculation.
5. Opportunities for influence
As the owner, you have little influence on the municipality's IMU rate (unless you are politically active) and even less on national factors. However, you can review and, if necessary, contest the cadastral assessment by checking the number of rooms and the property's categorization and classification. The categorization and classification can be checked, in particular, by comparing it to similar properties within the municipality. If similar properties (similar construction type, similar features) are classified differently than yours, you should be suspicious.