Practical guide
How thousandths (millesimi) shape your condominium instalments
Every time the condominium incurs a common expense, that cost is divided among the owners according to thousandths (millesimi), the proportional shares that measure the value of each unit against the whole building. Your number of thousandths is therefore the factor that, multiplied by the total expense, determines what appears in your instalment. Understanding how to read this proportion, which tables apply to which expenses and how to verify the calculation puts you in a position to check every charge and to spot a wrong allocation at once. This guide explains simply the link between thousandths and the amount of your instalments.
What thousandths are and why they exist
Thousandths express, on a base of one thousand, the proportional value of each property unit against the value of the whole condominium. The sum of all the units' thousandths is one thousand. They serve to allocate proportionally both the common expenses and the weight of votes at the meeting, so that those with a higher-value property contribute more and count for more in decisions.
Article 1123 of the Italian Civil Code sets the principle: the expenses needed for the preservation and enjoyment of the common parts are borne by the owners in proportion to the value of each one's property, unless otherwise agreed. That proportional value is exactly what the thousandths tables translate into figures, and it is the basis for calculating almost all your ordinary instalments.
How thousandths become the instalment amount
The mechanism is a proportion. If a common expense amounts to a certain total and your unit has a given number of thousandths, your share is obtained by multiplying the total by your thousandths and dividing by one thousand. A flat with more thousandths pays a larger share of the same cost, a flat with fewer thousandths pays a smaller share.
The instalments you pay during the year are generally fractions of the annual budget already allocated by thousandths: the total charged to you is divided by the number of due dates set. At year-end, the balancing adjustment compares what you paid with what is due on the final statement, always calculated on your thousandths. This is why an error in the thousandths spreads to every instalment.
Not all expenses use the same table
The general ownership table is not the only one. Some expenses follow specific tables or criteria. The maintenance and reconstruction expenses for stairs and lifts, under Article 1124 of the Italian Civil Code, are allocated half by the value of the units and half in proportion to the floor height. The expenses for a roof terrace in exclusive use follow Article 1126. Some expenses, such as water or heating, can also be based on consumption.
This means your account statement may show items allocated with figures different from those of the general table. That is normal and correct: each expense must follow the criterion set by law or by the regulation. When you check an instalment, always verify which table was applied to that specific item, because comparing everything against the general table alone leads to wrong conclusions.
How to check your allocation is correct
To check an instalment you need three figures: the total expense allocated, the table applied and your thousandths in that table. Redo the proportion and compare the result with the amount charged. A tiny difference may come from rounding the cents; a significant difference is a sign to clarify with the manager.
Also check that your thousandths are the right ones. If you bought recently, if units have been split or merged, or if the tables have been revised, the value may have changed. The revision or correction of the tables is governed by Article 69 of the implementing provisions of the Italian Civil Code, which sets out the cases in which the values can be changed even without everyone's consent.
Reading thousandths with the help of the platform
Doing these checks by hand is possible but laborious, especially when there are many tables. A management platform links each expense to the correct table and shows the owner, in their account statement, both the thousandths applied and the calculation that leads to the amount, row by row. That way you can understand not only how much you pay, but why you pay that figure.
AmministraPro presents the owner with the accounting position detailing the allocation by table and by expense item. On the /funzioni page you can see how thousandths tables and automatic allocations work, while /prezzi describes the plans for managers and firms. Having the transparent calculation in front of you is the simplest way to check that your thousandths are correctly applied to every instalment.
Frequently asked questions
If an owner does not pay, do my thousandths increase?
No, your thousandths do not change: they stay tied to the value of your unit. What can happen is that, to meet expenses in the presence of arrears, the manager asks all owners for advances in proportion to their thousandths, later recovering the sums from the defaulter. This is not an increase in your ownership share but a temporary advance. Sharing the defaulter's debt among the other owners happens only in specific cases and always in proportion to the respective thousandths.
Can I dispute the thousandths if I believe they are wrong?
Yes, but following the rules. The revision or correction of the thousandths tables is provided by Article 69 of the implementing provisions of the Italian Civil Code, which allows a change when an error emerges or when the conditions of a part of the building alter significantly the ratio between the values. If you believe your thousandths do not reflect the real value of your unit, you can raise the issue at the meeting and, in the cases provided, seek revision through the courts.
Why do some items on my instalment not follow the general table?
Because the law provides different allocation criteria depending on the type of expense. Stairs and lifts follow Article 1124, which splits them half on value and half on floor height; a roof terrace in exclusive use follows Article 1126; some expenses such as water and heating can be based on actual consumption. It is correct that your account statement shows different tables: each expense must follow the criterion set by law or by the condominium regulation.
How do I find out how many thousandths my unit has?
Your unit's thousandths are shown in the thousandths tables attached to the condominium regulation and are used in every allocation. You can ask the manager, who has the duty to keep and make available the management documents. In an owner portal your thousandths, split by table, are usually visible together with the account statement. Knowing this value lets you independently redo the calculation of any instalment and verify it is correct.
Is a small difference between my calculation and the instalment an error?
Not necessarily. Allocation involves rounding the cents, because the sum of the owners' shares must match the total expense exactly. This can produce differences of a few cents between your theoretical calculation and the amount charged, often concentrated on a single unit that absorbs the remainder. A gap of a few cents is therefore normal. A significant difference, on the other hand, should be clarified with the manager by asking for the detail of the expense, the table and the thousandths applied.
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