New rental indexation rules in Wallonia: What is changing for shared housing in 2026

Are you sharing a large home in Namur or a cozy apartment in Liège? Whether you are a host or a tenant, the question of rent indexing comes up every year. At Roomlala, we know how stressful and confusing this subject can be, especially since the recent energy reforms. By 2026, the Walloon rental landscape has well absorbed the previous crises, but the rules left in their wake continue to dictate the law. Between the famous EPC (Energy Performance Certificate), the correction mechanism, and the specifics of shared housing, it is sometimes difficult to find your way around. Today, we offer a complete and human-focused breakdown to understand exactly how rent indexing works for shared housing in Wallonia this year. Follow the guide!

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

The return to indexing for all dwellings

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

This measure marks a return to normalcy for landlords, who can once again adjust their rental income in the face of inflation. However, this return to normalcy does not mean that the EPC has lost its importance; quite the contrary. The Walloon legislature has implemented sustainable safeguards to prevent tenants of poorly insulated properties from facing a brutal rent increase that would catch up with the 2022-2023 freeze year all at once.

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

It is therefore crucial to know the exact EPC score of the dwelling you occupy or rent. An EPC A, B, or C certificate allows for standard indexing. Conversely, if the shared housing is located in a building rated D, E, F, G, or lacks a certificate, the rules of the game change thanks to what is called the correction mechanism, which remains fully applicable in 2026.

The correction mechanism: how does it work?

The correction mechanism is a specific mathematical formula introduced by the Walloon Region. Its goal? To smooth the impact of the freeze year (2022-2023) for energy-inefficient dwellings. If this mechanism did not exist, a landlord of an EPC F dwelling could currently apply indexing based on the cumulative inflation of recent years, which would cause an unsustainable rent increase for tenants from one month to the next.

In 2026, if your shared housing displays an EPC 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 softer and more controlled manner than with an EPC 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. The base rent was 900 euros. Without the correction mechanism, classic indexing might have driven the rent up to 980 euros in 2026. Thanks to the correction 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 rigor. We regularly notice at Roomlala that hosts, in good faith, attempt to apply classic indexing to an EPC E property, ignoring the continued existence of this correction mechanism in 2026. It is therefore the duty of each party to verify the EPC letter before accepting or proposing a new rent amount.

Indexing rules specific to shared housing in Wallonia

A legal framework aligned with the primary residence lease

Since September 1st, 2018, Wallonia has equipped itself with a specific legal framework for shared housing, finally recognizing this increasingly popular lifestyle. What you need to know in 2026 is that the indexing rules applicable to shared housing leases are strictly identical to those of standard primary residence leases. There is no preferential regime or penalty for tenants.

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

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

A frequent use case concerns the replacement of 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 indexing. 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 prerequisite: lease registration

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

Lease registration is a free administrative process that must be carried out by the host within two months following the signing of the contract, via the SPF Finances online platform, MyMinfin. This formality gives the contract a certain date 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's sale).

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, he sends them a letter to index the rent. The tenants, well-informed, ask him for proof of the lease registration. The host realizes he forgot this step. Result: he cannot index the rent. He must first register the lease (potentially with a late fee) before being able to formulate a new request.

We therefore strongly advise you, as soon as you move in, to verify that this formality has been completed. At Roomlala, we make it a point of honor to inform our hosts of their legal obligations to guarantee peaceful rentals without unpleasant surprises for tenants.

Hosts and tenants: Procedures and points of vigilance

Indexing is never an automatic process. It is a crucial point of vigilance. The host must mandatorily formulate their indexing request in writing to the tenants. A simple oral 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 the indexing on the anniversary date? Walloon law is lenient but sets strict limits. The retroactivity of indexing is limited to the 3 months preceding the request. For example, if the anniversary date of the shared housing is February 1st, but the host only sends their request on June 15th, they can only claim the indexed rent for the months of March, April, and May, in addition to future months. February and previous months are lost to them.

Another major point of vigilance concerns the validity of the EPC certificate. To benefit from classic indexing without the correction mechanism (for example, if the host has performed insulation work to move from an EPC E to an EPC C), the new EPC certificate must be valid at the precise moment of the indexing request. It is not enough to promise that the work is finished or that the certifier is coming.

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 must apply the correction mechanism related to the old EPC. Paperwork must always precede action!

How to calculate the indexing without making mistakes (and avoiding disputes)?

The calculation of indexing 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 that of the month preceding the signing of the contract, and the new index is that of the month preceding the anniversary date. However, with the introduction of the correction mechanism for lower EPCs, 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 dwelling is subject to the correction 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 steps toward the official Belgian government calculator: the Statbel calculator (statbel.fgov.be). This online tool, free and updated in real-time, automatically integrates the rules specific to Wallonia, including the parameters of the correction mechanism linked to the EPC score of your dwelling in 2026.

• Step 1: Gather your lease (for the signing and effective date), the amount of the base 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 indexing.

By proceeding in this way, the host proves their good faith, and the tenant is reassured about 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.