Free tool
For developers, architects, managing agents and co-owners: calculate each unit's share under Law No. 18-00 (private areas) or with agreed coefficients, the special shares, the votes and the allocation of the budget. Exact rounding, CSV and PDF export.
All calculations run in your browser: no data is sent. Your entries are kept on this device until you click “Clear”.
What the law says
Law No. 18-00 on the status of co-ownership of built properties, amended by Law No. 106-12 (2016) and Law No. 39-24 (2024). The official text is in Arabic; the quotations below are our translation of the French version published by the ANCFCC.
Unless the title deeds provide otherwise or the general meeting decides otherwise, each co-owner's share in the common parts is set according to the area of their private part in relation to the area of all the private parts of the building at the time the co-ownership is established.
For a project built in successive stages, the share may be set provisionally for the completed part, then definitively on completion (para. 2).
The regulation sets each owner's share of the charges according to the undivided share attached to each private part (art. 9).
Everyone contributes to the charges for the conservation, upkeep and management of the common parts, and to the charges of the collective services and common equipment according to the usefulness of those services and equipment for each private part (art. 36).
The allocation of common charges may be changed only by a decision of the general meeting under Articles 21 and 24; failing that, it is set by the competent court at the request of a co-owner (art. 37). Article 21 requires a three-quarters majority of the votes.
A co-owner who considers their contribution higher than what they owe may ask the court for a review (arts. 35 ter and 38).
Each co-owner has a number of votes corresponding to their rights in their private part; the regulation states the number of votes of each private part.
The votes of an owner who exceeds half are reduced (art. 16 decies, 16 bis 9 in the Arabic text). The text is ambiguous: the tool shows the raw votes and, for information, the reduction provided for in the model regulation.
Model co-ownership regulation
Where there is no regulation, a model regulation applies (art. 8 of the law). It was set by Decree No. 2-17-354 of 23 October 2017 (Official Bulletin No. 6635 of 1 January 2018, in Arabic).
Its Article 5 contains the table allocating the private parts and their undivided shares: number of private and common parts, brief content, areas, share of the plot in m², undivided share, number of votes, use, remarks. The share is calculated as: area of the private part × n ÷ total area of the private parts, with n = 1,000 or 10,000.
Its Articles 52 and 53 repeat the two keys of the law: share for the conservation, upkeep and management of the common parts; usefulness for common equipment and collective services (caretaking, lift, intercom, security, central air conditioning, television reception, given as examples in Article 51).
How to use it
Prepare the list of units with their areas (co-ownership plans, descriptive statement or the architect's schedule).
Type the units, generate them by level or import a CSV file from your spreadsheet.
Building, staircase, lift, car park: attach the units concerned and choose the allocation key.
Legal method of Article 6, or agreed coefficients; base 1,000, 10,000, 100,000 or percentage.
Review the alerts, then download the table as CSV or PDF, or print it.
Frequently asked questions
Not under the legal rule: Article 6 only uses the area of the private part. Other criteria are possible only if the title deeds provide for them or the general meeting decides otherwise: this is the tool's weighted method, whose coefficients are set by you or by the meeting.
Yes if they form part of the unit's private part: the law defines private parts as the “built or unbuilt” parts belonging to each co-owner for their individual use (art. 2). In the legal method, the tool counts them at their area. Weighting (for example half the area) is possible only if the title deeds provide for it or the general meeting decides it.
Roofs intended for common use are common parts (art. 4): they are not included in the private area, even if the regulation reserves their use for one unit. Check how each area is classified on the plans and in the regulation.
Yes if it forms a separate unit with its own private part: enter it on a separate row. If it is attached to an apartment, it is an annex of that unit. Cellars intended for common use are common parts (art. 4).
Because the tool rounds by the largest remainder: it takes the whole part of each exact value, then gives the missing units to the units with the largest decimal parts. This method respects the proportions as closely as possible while giving an exact total.
According to its usefulness to each unit (art. 36, para. 2). Create a “Lift” group, attach the units served and choose a key: shares of the units served, equal parts or utility coefficients. The key and coefficients are a matter for the co-ownership regulation or the general meeting; the law sets no scale.
The allocation of common charges can be changed only by the general meeting (arts. 21 and 37, three-quarters majority) or, failing that, by the court. For a registered building, the regulation and its amendments are recorded at the land registry (arts. 11 and 50): get professional support.
No. It is a calculation and checking tool. The official table appears in the co-ownership regulation, with the areas from the plans prepared by a surveying engineer. See the guide Co-ownership: one land title per apartment.
Sources
Texts read on 30 October 2026. The tool applies no other numerical rule: the coefficients of the weighted method and the utility keys are entered by you.
Any amendments published after 22 August 2024 (date of the consolidated version consulted) could not be checked: consult the Official Bulletin before any official use.
Setting up a co-ownership
We survey the building level by level and prepare the co-ownership plans, the table of areas and the technical file, in Fez and the surrounding region.