New rent indexation rules in Wallonia: What changes for shared housing in 2026

Do you share a large house in Namur or a cosy apartment in Liège? Whether you are a host or a tenant in shared housing, the question of rent indexation comes up every year. At Roomlala, we know how stressful and confusing this subject can be, especially following recent energy reforms. In 2026, the Walloon rental landscape has well and truly digested previous crises, but the rules left in their wake continue to dictate the law. Between the famous EPC (Energy Performance Certificate), the corrective mechanism, and the specifics of shared housing, it can sometimes be difficult to find your way around. Today, we offer you a complete, human-friendly guide to understanding exactly how rent indexation in shared housing works in Wallonia this year. Follow the guide!

The end of the indexation freeze and the importance of the EPC in 2026

The return to indexation for all types of housing

Remember: at the height of the energy crisis, the Walloon government decided to freeze or limit rent indexation for homes considered energy inefficient. The goal was to protect tenants from a double blow: exorbitant energy bills coupled with a rent increase. Since 1 November 2023, this strict freeze has ended. Today, in 2026, the general rule is back: 100% rent indexation is once again authorised in Wallonia, regardless of the Energy Performance Certificate (EPC) score of your home.

This measure marks a return to normal for landlords, who can once again adjust their rental income in the face of inflation. However, this return to normal does not mean that the EPC has lost its importance—quite the contrary. The Walloon legislature has put in place lasting safeguards to prevent tenants of poorly insulated properties from suffering a brutal rent increase that would make up for the 2022-2023 freeze in one go.

At Roomlala, we always encourage transparency. For tenants in shared housing, this means that an annual increase is now possible and legal, even if your bedroom's insulation leaves something to be desired. For hosts, it is the assurance of being able to maintain the profitability of their property, provided they follow very precise calculation formulas.

It is therefore crucial to know the exact EPC score of the property you occupy or rent. An EPC score of A, B, or C allows for standard indexation. Conversely, if the shared housing is located in a building rated D, E, F, G, or has no certificate at all, the rules of the game change thanks to what is known as the corrective mechanism, which remains fully applicable in 2026.

The corrective mechanism: how does it work?

The corrective mechanism is a specific mathematical formula introduced by the Walloon Region. Its purpose? To smooth out the impact of the freeze year (2022-2023) for energy-inefficient housing. If this mechanism did not exist, a host of an F-rated EPC property could currently apply indexation based on the cumulative inflation of the last few years, which would cause an unsustainable rent increase for tenants from one month to the next.

In 2026, if your shared housing has an EPC of D, E, F, G, or has no certificate, the host must use this corrected formula. Concretely, the calculation takes into account the health index of the month preceding the lease anniversary date, but applies a reduction factor proportional to the freeze period. This allows the rent to increase, yes, but in a much gentler and more controlled way than with an EPC of A, B, or C.

Let’s take a concrete example: imagine a shared house of three students in Mons in a townhouse with an EPC E rating. The base rent was 900 euros. Without the corrective mechanism, standard indexation might have driven the rent up to 980 euros in 2026. Thanks to the corrective mechanism, the increase is reined in, and the new indexed rent will be closer to 935 euros. This is a major difference for a student budget!

This complex system requires great rigour. We regularly notice at Roomlala that hosts, in good faith, try to apply standard indexation to an E-rated property, unaware that this corrective mechanism is still in effect in 2026. It is therefore the duty of each party to check the EPC rating before accepting or proposing a new rent amount.

Specific indexation rules for shared housing in Wallonia

A legal framework aligned with the primary residence lease

Since 1 September 2018, Wallonia has had a specific legal framework for shared housing, finally recognising this increasingly popular way of living. What you need to know in 2026 is that the indexation rules applicable to shared housing leases are strictly identical to those for standard primary residence leases. There is no preferential regime or penalty for tenants in shared housing.

Whether you have signed a single lease (where all tenants are jointly liable) or individual leases for each room (often treated as a homestay or furnished room rental), the principle remains the same. Indexation can only occur once a year, at the earliest on the anniversary date of the lease agreement coming into effect.

It is important to emphasise that indexation applies to the rent excluding charges. Provisions for charges (water, gas, electricity, internet) are not indexed: they must be adjusted based on actual bills. At Roomlala, we always recommend clearly separating the base rent and charges in the contract to avoid any confusion during the annual calculation.

A frequent use case involves replacing a tenant. If an amendment is signed to acknowledge the departure of Julien and the arrival of Sarah, the anniversary date of the initial lease remains the reference for indexation. The host cannot take advantage of this change of tenant to index the rent at another time of the year or to bypass the rules related to the EPC.

The condition sine qua non: registration of the lease

Here is a vital piece of information that still escapes many market players in 2026: rent indexation for shared housing is only legally applicable if the lease agreement has been registered beforehand. This is an absolute condition imposed by Walloon law. An unregistered lease immediately deprives the host of their right to indexation.

Lease registration is a free administrative procedure that must be carried out by the host within two months of signing the contract, via the MyMinfin online platform of the FPS Finance. This formality provides a certain date for the contract and protects all parties. For tenants, it is the guarantee that their rights are enforceable against third parties (for example, in the event of the building being sold).

Let’s imagine a concrete case: a host in Tournai has been renting a house to four young workers for two years. In March 2026, they send a letter to index the rent. The tenants, being well-informed, ask for proof of lease registration. The host realises they have forgotten this step. Result: they cannot index the rent. They will first have to register the lease (potentially with a late fine) before being able to make a new request.

We strongly advise you, upon moving in, to check that this formality has been completed. At Roomlala, we make a point of informing our hosts of their legal obligations to ensure peaceful rentals without any nasty surprises for tenants.

Hosts and tenants: Steps to take and points to watch

Indexation is never an automatic process. It is a crucial point of vigilance. The host must mandatory make their indexation request in writing to the tenants. A simple verbal agreement or an informal message is not sufficient from a legal perspective. We recommend sending a clear email with a read receipt, or better yet, a registered letter detailing the exact calculation and the new amount due.

What happens if the host forgets to request indexation on the anniversary date? Walloon law is lenient but sets strict limits. The retroactivity of indexation is limited to the 3 months preceding the request. For example, if the anniversary date of the shared housing is 1 February, but the host only sends their request on 15 June, they will only be able to claim the indexed rent for the months of March, April, and May, in addition to future months. The months of February and earlier are lost to them.

Another major point of vigilance concerns the validity of the EPC certificate. To benefit from standard indexation without the corrective mechanism (for example, if the host has carried out insulation work to go from an EPC E to an EPC C), the new EPC certificate must be valid at the precise moment of the indexation request. It is not enough to promise that the work is finished or that the certifier is going to visit.

Here is a typical use case: a host renovates their shared house in Louvain-la-Neuve in January 2026. The lease anniversary date is in March. If they have not received the official EPC document certifying class C before sending their request in March, they will have to apply the corrective mechanism linked to the old EPC. Paperwork must always precede action!

How to calculate indexation without making mistakes (and avoid disputes)?

The calculation of indexation is based on a strict legal formula that uses the evolution of the health index. The basic formula is as follows: (Base rent x New health index) / Base health index. The base index is the one from the month preceding the signing of the contract, and the new index is the one from the month preceding the anniversary date. However, with the introduction of the corrective mechanism for lower EPC ratings, this manual calculation has become a real headache.

Faced with this complexity, it is imperative to use the right tools. At Roomlala, we formally advise against trying to do the calculation yourself if your housing is subject to the corrective mechanism. The slightest decimal error or the wrong choice of index can lead to unnecessary disputes between tenants and hosts, poisoning the atmosphere of the house.

The safest and most transparent solution is to direct all your efforts towards the official calculator of the Belgian government: the Statbel calculator (statbel.fgov.be). This online tool, which is free and updated in real time, automatically integrates the specific rules for Wallonia, including the parameters of the corrective mechanism linked to the EPC score of your home in 2026.

• Step 1: Gather your lease (for the signature and effective date), the amount of rent excluding charges, and the EPC certificate.
• Step 2: Go to the Statbel website and enter this data into the simulator.
• Step 3: Generate the official PDF document provided by the site.
• Step 4: Attach this PDF to your written request for indexation.

By proceeding in this way, the host proves their good faith, and the tenant is reassured as to the accuracy of the amount claimed. At Roomlala, we firmly believe that transparent communication, supported by official tools, is the key to a harmonious and sustainable shared housing experience.