NL
EN
FR
Belgium
Back to articles

New Brussels regulations on excessive rents: What Landlords Need to Know

April 29, 2025

On 4 April 2025, the Brussels Regional Parliament approved a new ordinance that has significant implications for landlords in the region. This ordinance ends the deferred implementation of certain provisions from the ordinance of 28 October 2021. Its main objective: combating excessive rents. The new rules will enter into force on 1 May 2025.

New Brussels regulations on excessive rents: What Landlords Need to Know

This measure applies to all lease agreements, including those signed before or on the date of its entry into force.


The Rent Assessment Commission: a key player

At the heart of this system is the Rent Assessment Commission, a neutral body with equal representation of landlords and tenants. The commission provides non-binding, yet objective advice on the fairness of a rent.

Requests are processed within two months. The commission’s opinions are publicly accessible and freely available on its website.

The commission may also act as a mediator and aims to encourage out-of-court settlements.


What Is a “reference rent”?

The reference rent is an indicative rental value based on objective parameters such as:

  • Surface area
  • Year of construction
  • Location within the region
  • Amenities such as central heating, additional bathrooms, garage, storage space
  • Energy performance level

The primary aim of these reference rents is to provide prospective tenants and landlords with a clear picture of Brussels rental prices.

Since the end of 2021, landlords must include the reference rent in the lease agreement. As of November 2024, it must also be mentioned in advertisements.

An online simulator is available on the Brussels Region website to calculate the reference rent, including a 10% margin to allow for negotiation.


What is considered an excessive rent?

A rent is deemed excessive if it exceeds the reference rent by more than 20%, without quality defects or exceptional circumstances to justify the difference.

In such a case, the tenant may request a revision from the Rent Assessment Commission, and possibly also through the justice of the peace.


Revision procedures for short and long-term leases

The ordinance provides different procedures depending on the duration of the lease:

  • Short-term (1 to 3 years): a request for revision can be filed starting two months after the lease takes effect.
  • Long-term: a request can only be filed starting three months after the lease takes effect.

After receiving the commission’s advice, the parties may reach an agreement through mediation. If this fails—or if the parties prefer—they may turn to the courts. The judge will decide based on fairness and may retroactively adjust the rent, up to four months prior to the request.

Note: if a landlord has previously had to revise an excessive rent for the same property, a new request may be submitted at any time during the lease. If the rent is again found to be excessive, the revised rent will apply from the first month of the lease.


Possibility of rent increase at the landlord’s request

The regulation also allows the judge to grant a rent increase when:

  • The reference rent has increased by at least 20% compared to the current rent, and
  • There are no quality defects justifying a lower rent.

An increase is also possible when:

  • The rent is at least 10% below the reference rent,
  • The landlord has carried out non-mandatory works (outside Article 220 of the BHC), and
  • There are no defects.

This mechanism is intended to encourage landlords to manage their properties sustainably and responsibly.


Conclusion

As a landlord in Brussels, you can no longer set your rental prices entirely freely. You must be aware that your rent can be reviewed if it is considered excessive. Not every excessive rent will be automatically revised, but you will now have to justify it.

The Real Estate team at Andersen is here to support you. Should you have any questions on this subject, please do not hesitate to contact our specialists at info@be.Andersen.com or +32 2 747 40 07.

Discover more about this topic?

I am looking for a specialist in

See more articles

We are pleased to announce several important developments that will further strengthen Andersen in Belgium’s M&A and commercial law capabilities as of January 2026.

19.01.2026

We are pleased to announce several important developments that will further strengthen Andersen in Belgium’s M&A and commercial law capabilities as of January 2026.

First, we are pleased to announce that the West Flanders team of Philippe & Partners has joined Andersen in Belgium. Based in Roeselare, the team is led by Partner Dirk Clarysse, together with Charlotte Romaen, Senior Counsel.

Read the article »
Court of Cassation confirms the personal disciplinary liability of each individual real estate agent, including those operating within a real estate group
News

14.01.2026

Court of Cassation confirms the personal disciplinary liability of each individual real estate agent, including those operating within a real estate group

By judgment of 18 December 2025, the Belgian Court of Cassation delivered a significant ruling in a disciplinary (disciplinary law / professional disciplinary proceedings) case against a real estate agent, with far-reaching consequences for the real estate profession.

Read the article »
Construction Law & Liability of the Architect

13.01.2026

Construction Law & Liability of the Architect

In an important judgment of 19 December 2025 (C.25.0192.F), the Court of Cassation emphasized the fundamental importance of the architect’s duty of supervision when selecting the contractor, in particular with regard to the contractor’s access to the profession.

Read the article »
Autonomous guarantee finally enshrined in law
News

13.01.2026

Autonomous guarantee finally enshrined in law

With Book 9 of the Civil Code, the autonomous guarantee - also known as a bank guarantee or guarantee on first demand - now has, for the first time, a clear statutory basis in Belgium. Until now, this legal instrument was primarily shaped by case law, customary practice, and international soft law. With regard to the latter, reference is often made to the so-called URDG 758 (Uniform Rules for Demand Guarantees), a set of practical rules drawn up by the International Chamber of Commerce (ICC). These rules are not binding as such, but they are frequently used in (inter)national trade because they provide uniform and recognizable arrangements and thus legal certainty.

Read the article »