Market
Published on 1 October 20266 min read
Rental agreement in Belgium: required clauses
The Immolytics editorial team
A lease for a main residence in Belgium must be in writing and contain a set of required details: who the parties are, the start date, the duration, the rooms being let, the rent and the charges. The rules depend on the region the property is in: the Walloon decree of 15 March 2018, the Brussels Housing Code, and in Flanders the decree of 9 November 2018 (Vlaams Woninghuurdecreet). The landlord must also draw up an entry inventory of fixtures with the tenant, register the lease and hold an energy performance certificate.
What a rental agreement must contain
In all three regions, a lease for a main residence must be in writing. If one party refuses to sign a written contract, the other can send a formal notice by registered letter, then ask the justice of the peace to impose one. Regional law sets out what the lease must contain at the very least:
- the full identity of landlord and tenant (name, first two given names, address), and for a company, its name and company number;
- the start date and the duration of the lease;
- a description of every room and part of the building being let;
- the rent, excluding charges;
- the charges: what they are, how much, and whether they are a fixed amount or advance payments;
- in Wallonia and Brussels, whether the meters are individual or shared.
Each region adds its own items. In Wallonia, the lease states the date of the latest energy performance certificate and the rating it gives the property. In Brussels, it states the reference rent for the property, which you can look up on loyers.brussels. In Flanders, it refers to the explanatory note published by the Flemish government. In Wallonia and Brussels, an official explanatory annex setting out both parties' rights and duties must be attached to the lease.
Clauses that prevent disputes
Some clauses are not required by law, but they prevent most disagreements. They deal with money and upkeep:
- charges: which items the tenant pays and how the landlord accounts for them;
- rent indexation, or a clause ruling it out;
- the rental deposit: its amount and its form;
- routine upkeep and minor repairs for the tenant, and major repairs that stay with the landlord;
- subletting, pets and any works the tenant would like to carry out;
- the tenant's fire insurance.
Indexation works the same way in all three regions. Unless the lease rules it out, the rent can be adjusted once a year, on the anniversary of the lease, in line with the health index. The formula is set by law: base rent multiplied by the new index, divided by the starting index. The landlord must ask for it in writing and can only claim it back for the three months before the request. The lease must be in writing. In Wallonia and Brussels it must also be registered, and in Brussels the landlord must have given the tenant a valid energy performance certificate.
Some clauses have no effect even if the tenant signed them, because the regional rules are mandatory. An indexation above the legal formula is cut back to it. A deposit above the regional ceiling cannot be demanded. In Wallonia and Flanders, the fees of an agency hired to let the property cannot be charged to the tenant, unless the tenant hired the agency. In Brussels, a clause forbidding the tenant to register their address at the property is not valid.
Rental rules differ by region
Since the sixth state reform, residential leases have been a regional matter. The principles are similar, but the details differ: a lease drafted for a flat in Brussels does not work as it stands for a house in Namur or Ghent.
A rental deposit is not compulsory, but if the lease asks for one, the amount is capped. In Wallonia it cannot exceed two months' rent since 1 June 2023, whatever its form: a blocked account in the tenant's name, a bank guarantee, or a guarantee arranged with the help of the CPAS. In Brussels the ceiling is also two months' rent for leases signed or renewed since 1 November 2024. In Flanders it is three months' rent. Interest on a blocked account belongs to the tenant, and the deposit is only released with the written agreement of both parties or a court decision.
An entry inventory of fixtures is compulsory in all three regions. Landlord and tenant draw it up together and in detail, either while the property is still empty or during the first month of occupation. In Wallonia and Flanders, the cost of an expert appointed jointly is shared. The inventory is attached to the lease and registered with it. Without an entry inventory, the tenant is presumed to have received the property in the condition in which they hand it back, so it is up to the landlord to prove any damage.
Registering the lease is the landlord's job. It must be done within two months of signing, and it is free within that period. In Wallonia and Flanders this goes through MyRent, the application of the federal finance ministry. Brussels opened its own platform, IRISrent, in January 2025, and since a ruling of the Constitutional Court in April 2025 the region asks landlords to register on both IRISrent and MyRent. An unregistered lease is still valid between landlord and tenant, but the tenant can then leave without notice or compensation (in Wallonia, after giving the landlord one month's formal notice to register it). In Wallonia and Brussels, the landlord cannot index the rent either.
An energy performance certificate is required before a property is put up for rent, in all three regions. In Wallonia its date and rating appear in the lease itself. In Brussels the landlord hands it to the tenant at the latest when the lease is signed. In Flanders, where it is called the EPC, a copy is attached to the lease. Our page on the energy performance certificate explains what it measures, and the energy comparison tool lets you compare the consumption of two properties.
Main residence, commercial and other leases
The rules in this article apply to a lease for a main residence, the home where the tenant mainly lives. Other leases have their own rules, their own duration and their own ways of ending.
The main residence lease runs for nine years, unless the parties sign a written short-term lease, which cannot last more than three years in total. The commercial lease covers premises used for a shop or a business. The student lease covers a student's accommodation during their studies, with its own rules in each region. The emphyteutic lease is not an ordinary tenancy: it grants a long-term property right.
Setting the rent: check your position
The starting rent is in principle agreed freely between landlord and tenant. In Brussels, however, the lease must state the reference rent for the property, and Wallonia also publishes an indicative rent grid. Comparing the rent you have in mind with these references helps you avoid a gap that is hard to justify.
Our rent estimator gives a first idea for your property. The property prices by municipality, the price evolution page and the market trends place the property within its market. To find out what the property itself is worth, request a valuation. For a question about our data, use the contact page.
Frequently asked questions
Does a main residence lease have to be in writing?
Yes. The Walloon decree, the Brussels Housing Code and the Flemish decree all require a written lease. A verbal tenancy is not void for that reason, but either party can demand a written contract and, if the other refuses, go to the justice of the peace.
How much can the rental deposit be?
Two months' rent in Wallonia, whatever the form of the deposit, and two months in Brussels for leases signed or renewed since 1 November 2024. In Flanders the ceiling is three months' rent.
Can the landlord raise the rent during the lease?
The landlord can index the rent once a year, on the anniversary of the lease, using the health index and the legal formula, provided they ask for it in writing. In Wallonia and Brussels the lease must also be registered. Apart from indexation, the rent can only be revised at set points in the lease, by agreement between the parties or by the justice of the peace.
Stay informed about the real estate market
Receive trends, analyses and new tools by email.
No spam. Unsubscribe in one click.