Practical guide
How to split condominium expenses by thousandths
Anyone managing or living in an Italian condominium eventually runs into the same question: why do two owners of similar apartments pay different shares for the same expense, or why isn't the elevator billed the same way as the roof. The answer lies in Article 1123 of the Italian Civil Code and in the millesimal tables every building should have on file. This guide explains, with concrete examples, when the general ownership share applies, when actual or potential use of an asset matters instead, and how management software can make these calculations traceable rather than left to a spreadsheet nobody checks after the first year.
The Article 1123 principle: proportionality, not equality
Article 1123 of the Italian Civil Code establishes that expenses necessary for the preservation and enjoyment of common areas, for the administrator's services, and for other ordinary management costs are borne by owners in proportion to the value of their individual property, unless otherwise agreed. That value is expressed in thousandths, calculated from the general millesimal table, which reflects the ratio between the value of each unit and the total value of the building.
Proportionality does not mean everyone pays the same way: it means an owner whose property is worth twice as much as a neighbor's pays, all else equal, twice the share of general expenses. The second paragraph of the same article introduces a crucial exception: when a building has multiple staircases, courtyards, roof terraces, structures or systems serving only part of the whole building, maintenance costs for those elements fall only on the group of owners who benefit from them.
General versus particular expenses: the distinction that changes everything
In everyday practice, the distinction between general and particular expenses is what generates the most disputes at owners' meetings. General expenses, such as stairwell cleaning, administration fees, building insurance, and roof maintenance when it serves the entire structure, are split by general ownership thousandths under the first paragraph of Article 1123.
Particular expenses instead follow different criteria set out in specific articles: the elevator is split half by ownership thousandths and half by each unit's floor height (Article 1124); centralized heating is split by actual consumption where heat meters are installed, with a residual share allocated by thousandths for involuntary heat loss, under the energy efficiency rules introduced by Legislative Decree 102/2014; and stairs or elevators serving only some floors are split only among the owners who benefit. An administrator who defaults to general thousandths for everything, out of convenience, exposes the building to well-founded legal challenges.
- General expenses (cleaning, administration, insurance): general ownership thousandths, Article 1123 paragraph one
- Elevator: half ownership thousandths, half floor height, Article 1124
- Centralized heating: actual consumption plus a residual share for heat loss, where metered
- Assets or services serving only part of the building: split only among the owners concerned, Article 1123 paragraph three
Common disputes in practice
The most frequent case involves ground-floor units and shops: owners on the ground floor often object to paying for the elevator, and Article 1124 does in fact account for floor height, so a ground-floor shop pays a minimal or zero share of the height-linked component while remaining liable for the ownership-thousandths component. Another recurring case is the attic or a pertinent garage box, which has its own thousandths and does not contribute to stairwell expenses unless it is accessed through them.
Once approved, millesimal tables are neither permanent nor freely changeable: Article 69 of the implementing provisions of the Civil Code allows revision only when the tables were drawn up in error, or when the factual conditions of the building have materially changed, for instance through additional floors or changes in surface area. A revision not grounded in one of these circumstances can be legally challenged.
Why automating the allocation genuinely pays off
Manually calculating dozens of allocation statements, one per table (general, elevator, heating, stairs), and cross-referencing them against every owner's payments is work that generates human error precisely in the larger buildings where disputes carry the most weight. A tool like AmministraPro automatically applies the correct millesimal table based on the nature of each expense, generates the allocation statements, and keeps a payment history for every owner, making it possible to verify at any time which criterion was used for a given expense item.
This does not replace the administrator's judgment on which table applies to a borderline expense, but it eliminates calculation errors and manual reconstruction when a statement is disputed, a benefit especially valued in larger multi-building complexes with differentiated tables per staircase.
Frequently asked questions
Who decides which millesimal table applies to a given expense?
Classifying an expense as general or particular follows from the nature of the asset or service and from the Civil Code provisions, mainly Articles 1123 and 1124, not from the administrator's discretion. The administrator applies the criterion set by law or by a contractual condominium regulation if one provides for different criteria; if disputed, the final say rests with a court.
Can an owner refuse to pay an expense because they do not use the asset?
No, except in the specific cases set out by the Civil Code where an asset serves only part of the building (Article 1123 paragraph three). For common parts by nature, such as foundations or a roof serving the entire structure, the share is owed regardless of actual use, because the co ownership link ties the expense to ownership, not to concrete use of the asset.
How is a millesimal table believed to be wrong corrected?
It can be changed by a qualified majority resolution when all owners agree on the new values, or, under Article 69 of the implementing provisions, through a technical assessment demonstrating an original error or a material change in the building's conditions. In the latter case a simple majority of the meeting may suffice, but a report from a qualified professional is still required.
Is centralized heating always billed by consumption?
Only where technically feasible: Legislative Decree 102/2014 made the installation of heat metering systems mandatory in buildings with centralized systems, where technically possible and economically viable. Where installed, the cost is split between a share for actual metered consumption and a residual share for involuntary heat loss, allocated according to thermal need thousandths rather than general ownership thousandths.
Can condominium management software get the allocation wrong?
A tool like AmministraPro automatically applies the criteria configured for each loaded millesimal table, so the arithmetic is reliable given correct input data. Responsibility still rests with the administrator to choose the right table for each expense item and to verify that the loaded thousandths match those approved at the owners' meeting or filed in the condominium regulation.
Try AmministraPro
Accounting, thousandths-based cost splitting, meetings, communications and artificial intelligence in a single Italian software, compliant with UNI 10801 and GDPR.