2026 rent indexation in Brussels: EPC and shared housing rules

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

The 3 golden rules for rent indexation Brussels 2026

The written and registered lease: an essential 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, although 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 stakeholders. At Roomlala, we make it a point of honour to secure your procedures by reminding you of the importance of this fundamental document.

Read also: Rental guarantee in Flanders 2026: The new rules for renting a room long-term, Rising rental costs in Switzerland (Winter 2026): Renting out a room to balance your budget and Shortage of student accommodation in Belgium in 2026: Homestay, the supportive 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 a room in your home to a student for a year. If you have never bothered to register the lease on the government's MyRent platform, you will not be able to apply 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 obligation often forgotten in shared housing

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

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

At Roomlala, we notice that this oversight is the primary cause of disputes during indexation. For example, if a landlord demands a rent increase but the tenant has never seen the EPC, the latter is entitled to flatly refuse the increase. Make sure 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 itself. The landlord must mandatorily request it in writing from 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 due.

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 as not to miss this crucial step.

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

The end of the strict cap for energy-inefficient homes

Remember: in the midst of the energy crisis, the Brussels government had 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 whammy of inflation and exorbitant energy bills. However, it is essential to note that this strict freeze ended in October 2023.

Today, in 2026, it is again possible 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 anyhow for older contracts.

The transition was designed to avoid too violent a financial shock 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 if your accommodation is not at the top of the class in terms of energy. This is where the concept of a correction factor comes in.

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

For rent indexation Brussels 2026, a specific mechanism, called the 'correction factor', remains applicable. It exclusively concerns housing with an EPC class E, F, or G whose lease contract began before 14 October 2022. The objective of the region is to avoid a brutal rise in rent that would make up for the inflation of the frozen years in one go.

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 little 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 a room since 1 September 2021 in an apartment with an EPC F. In September 2026, you wish to index the rent. You will not be able to simply multiply the base rent by the new index of 2026. You will have to apply the formula integrating the correction factor which neutralises the period of exceptional inflation of 2022-2023. 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 long-term: same rules as an entire home

When discussing shared accommodation, a persistent misconception suggests that renting a single 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 legislation on residential leases of the Brussels-Capital Region.

This means that all the indexation rules mentioned above 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 our community is informed so that the sharing economy remains fair and legal.

Whether you have a joint tenancy 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.

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

The question of the EPC for shared housing in Belgium often raises questions. How to evaluate the energy performance of a single room? In reality, Brussels law is pragmatic: it is the EPC certificate of the entire housing unit that counts. If you rent 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 entire 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 work (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 linked to classes E, F, and G, thus adding value to your property while offering more comfort to your tenants.

Common errors and practical advice for hosts and tenants

Retroactivity limited to 3 months

One of the most frequent errors we observe among landlords is forgetting the anniversary date of the lease. 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 request for indexation on 15 July. You will be able to apply the new rent for the future, and you will only be able to claim the arrears for the months of April, May, and June (the 3 months preceding July). February and March are definitively lost for you. Good diary management is therefore essential!

How to calculate indexation without making a mistake?

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 cost you 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 date of signing the lease, the region (Brussels-Capital), and the EPC score. You just need to enter your contract data to obtain the exact and legal amount down to the cent.

• Step 1: Gather your lease (date of signature, date of entry into force, base rent excluding charges).
• Step 2: Check the score of your EPC certificate.
• Step 3: Go to the Statbel website and fill in 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 the Brussels tenancy legislation can seem complex, but it is there to balance the rights and duties of each person. 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, respect regional standards like the EPC, and communicate openly. A tenant well-informed about 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 wanting to make a vacant space profitable, Roomlala remains your partner of choice for navigating the world of peer-to-peer rentals in Belgium with peace of mind.