2026 Brussels rent indexation: EPC and rules for shared housing

Inflation and energy costs have deeply shaken up the Belgian property market in recent years. If you are a landlord or a tenant in the capital, you are surely asking yourself specific questions about the 2026 Brussels rent indexation. Between past rent freezes, Energy Performance Certificates (EPC), and the specificities of shared housing, it is very easy to get lost. At Roomlala, we know how crucial it is to rent with peace of mind and in compliance with the law. Whether you are offering a homestay or looking to rent a room long-term, understanding Brussels tenancy legislation is essential today. In this comprehensive article, we break down for you the legal rules applicable in 2026 for indexing a rent, with a particular focus on Belgium shared housing EPC. Get ready to become an expert on the subject and manage your rentals without the slightest stress!

The 3 golden rules for 2026 Brussels rent indexation

The written and registered lease: an unavoidable formality

To be able to index a rent in 2026, the very first condition required by the Brussels-Capital Region is the existence of a written lease agreement. Verbal agreements, even if they may have existed in the past, offer you no solid legal protection and prohibit any rent revision. Brussels law requires a clear document, dated and signed by all parties involved. At Roomlala, we make it a point of honour to secure your procedures by reminding you of the importance of this fundamental document.

See also: Rental security deposit in Flanders 2026: The new rules for renting a room long-term, Rise in rental costs in Switzerland (Winter 2026): Renting out a room to balance your budget and Student accommodation shortage in Belgium in 2026: Homestay, the community-minded alternative

Furthermore, this written lease must imperatively be registered with the Legal Security office (FPS Finance). This registration is a completely free procedure if it is carried out within two months following the signing of the contract. If you exceed this period, a fine may be claimed from you. A non-registered lease purely and simply deprives the landlord of their right to indexation, even if all other conditions are met.

Let's take a concrete example: you have been renting out a room in your home to a student for a year. If you have never taken the trouble to register the lease on the government's MyRent platform, you will not be able to apply the indexation on the anniversary date. It is therefore essential to regularise the situation as soon as possible to protect your rights as a host.

The EPC certificate: the often forgotten obligation in shared housing

The second condition, and not the least, concerns the well-known Energy Performance Certificate (EPC). To index the rent, a valid EPC certificate must have been communicated to the tenant, ideally at the signing of the lease. This is a major point of attention, because many landlords renting out a simple room often omit this procedure, thinking that it only applies to entire homes.

However, Brussels tenancy legislation is very clear: all rentals intended for a primary residence are concerned. Without the delivery of a valid EPC certificate to the tenant, indexation is strictly forbidden. If you are renting a room in your own house, it is generally the global EPC of the house that is authentic and that must be annexed to the shared housing or accommodation contract.

At Roomlala, we observe that this oversight is the primary cause of disputes during indexation. For example, if a landlord claims a rent increase but the tenant has never seen the EPC, the latter has the right to refuse the increase outright. Therefore, ensure you have this document up to date (it is valid for 10 years) and provide a copy to your tenant.

The written request: indexation is not automatic

Many landlords are unaware of this, but in Brussels, rent indexation is never automatic. Even if the anniversary date of the lease has passed, the rent does not adjust by itself. The landlord must mandatorily make the request in writing to the tenant. This rule applies to all types of leases, including for a homestay or shared housing.

This written request can take the form of a registered letter, an email (if the parties have agreed to communicate electronically in the lease), or a letter delivered by hand against a signature. The notification must clearly indicate the new rent amount and the date from which it is payable.

Imagine that your lease started on 1 March. On 1 March of the following year, it is up to you, the landlord, to take the initiative to send a message to your tenant to inform them of the new calculation. If you do not say anything, the tenant will legitimately continue to pay the old rent. At Roomlala, we advise you to set an annual reminder so you do not miss this crucial step.

The impact of the EPC on the calculation: No more freezes, make way for the correction factor

The end of the strict cap for energy-inefficient properties

Remember: in the midst of the energy crisis, the Brussels government decided to freeze or cap rent indexation for housing considered as energy-inefficient (EPC E, F, or G). This exceptional measure aimed to protect tenants against the double penalty of inflation and exorbitant energy bills. However, it is essential to note that this strict freeze has been over since October 2023.

Today, in 2026, it is possible once again to index the rents of poorly insulated housing. This news is often welcomed with relief by landlords who have seen their own costs increase without being able to adjust their rental income. However, this resumption of indexation does not happen just any way for old contracts.

The transition was designed to avoid a financial shock that was too violent for tenants. If the classic calculation formula is based on the health index (base rent x new health index / starting health index), a major subtlety is added to it if your housing is not top-tier in terms of energy. This is where the notion of a correction factor comes in.

The well-known correction factor for leases prior to mid-October 2022

For 2026 Brussels rent indexation, a specific mechanism, called a 'correction factor', remains applicable. It exclusively concerns housing with an EPC class of E, F, or G whose lease contract started before 14 October 2022. The region's objective is to avoid a sudden rise in rent that would catch up with the inflation of the freeze years all at once.

Using the classic formula alone is illegal for these specific leases. The application of the Brussels correction factor is mandatory. Concretely, this factor smoothes out the increase. The calculation becomes a bit more complex, which is why the Brussels authorities strongly recommend using the official rent calculator provided by Statbel.

Let's take a use case: you have been renting out a room since 1 September 2021 in an apartment with an EPC F rating. In September 2026, you want to index the rent. You will not be able to simply multiply the base rent by the new 2026 index. You will have to apply the formula integrating the correction factor which neutralises the period of exceptional 2022-2023 inflation. If you make a mistake, the tenant will be able to demand a refund of the overpayment.

Shared housing and homestays: What changes for Brussels tenancy legislation

Renting a room for the long term: the same rules as an entire home

When approaching the subject of shared accommodation, a persistent misconception suggests that renting a simple room escapes the strict rules of the classic property market. This is false. If you decide to rent a room long-term and the tenant establishes their primary residence there, you fall under the scope of the housing lease legislation of the Brussels-Capital Region.

This means that all the indexation rules mentioned previously apply to the letter. You cannot arbitrarily decide to increase the rent by 50 euros on the pretext that your expenses have increased, without respecting the health index formula and the conditions related to the EPC. At Roomlala, we ensure we inform our community so that the sharing economy remains fair and legal.

Whether you have a joint shared housing contract (several tenants on the same lease) or individual leases for each room, rigour is required. Indexation is calculated on the base rent excluding charges. Fixed or provisional charges are subject to a separate statement and are not subject to the same indexation formula.

Belgium shared housing EPC: how does it work in practice?

The question of the Belgium shared housing EPC often raises questions. How do you evaluate the energy performance of a single room? In reality, Brussels law is pragmatic: it is the EPC certificate of the global housing unit that is authentic. If you rent out three rooms in a single-family house, it is the EPC of the entire house that must be communicated to each flatmate.

If you are the owner of a large apartment divided into shared housing, you therefore only need one EPC certificate for the whole apartment. This score (from A to G) will determine whether or not you are subject to the correction factor when indexing the rents of your flatmates (for leases signed before October 2022).

It is important to note that if you undertake energy renovation works (insulation, boiler replacement, double glazing) while your tenants occupy the premises, it is in your best interest to have a new EPC certificate produced. A better score will allow you to exit the restrictions related to classes E, F, and G, thus valuing your property while offering more comfort to your tenants.

Common mistakes and practical tips for hosts and tenants

Retroactivity limited to 3 months

One of the most frequent mistakes we observe among landlords is forgetting the lease anniversary date. What happens if you realise in June that you should have indexed the rent in January? Can you claim the arrears since the beginning of the year? The answer is no, not in its entirety.

The law provides for retroactivity strictly limited to 3 months. In case of oversight, the landlord can only claim indexation for the 3 months preceding their written request, in addition to the current month. This rule aims to protect the tenant against sudden and unforeseen debts that could accumulate over several years.

Concrete example: the anniversary date of your lease is 1 February. You forget and send your written indexation request on 15 July. You will be able to apply the new rent for the future, and you will only be able to claim arrears for the months of April, May, and June (the 3 months preceding July). February and March are permanently lost for you. Good diary management is therefore essential!

How to calculate indexation without making a mistake?

The manual calculation of indexation can quickly become a headache, especially with the introduction of the correction factor for poor EPCs. A calculation error in your favour could be contested by the tenant, and an error in your disfavour would make you lose money. To avoid this, the safest method is to use the official tools.

We recommend that you systematically use the online rent calculator from Statbel, the Belgian statistical office. This free tool takes into account all regional subtleties, including the lease signature date, the region (Brussels-Capital), and the EPC score. You just need to enter the data from your contract to obtain the exact and legal amount down to the cent.

• Step 1: Gather your lease (signature date, start date, base rent excluding charges).
• Step 2: Check the score of your EPC certificate.
• Step 3: Go to the Statbel website and fill out the form.
• Step 4: Attach the PDF result generated by Statbel to the indexation request letter sent to your tenant for total transparency.

Security and support with Roomlala

At Roomlala, our mission is to facilitate the connection between hosts and tenants, while ensuring a secure framework for everyone. We know that Brussels tenancy legislation can seem complex, but it is there to balance the rights and duties of everyone. Renting a room in your own home or finding shared housing should never be a source of legal anxiety.

By using our platform for your medium and long-term rentals, you benefit from a trusted community. We always encourage our users to sign clear contracts, to respect regional standards such as the EPC, and to communicate openly. A tenant who is well-informed on how their rent is calculated will always be more inclined to accept a justified and legal indexation.

Do not hesitate to browse our other guides to optimise your rental experience. Whether you are a student looking for an affordable room or a landlord wishing to monetise an unoccupied space, Roomlala remains your partner of choice to navigate the world of peer-to-peer renting in Belgium with peace of mind.