EPC and rent indexation ban: guide by region

The link between EPC and rent indexation

Since 2022, the Belgian regions have progressively linked the right to index rent to the EPC (Energy Performance Certificate) score. The goal: to incentivise landlords to renovate the most energy-intensive properties by depriving them of a major financial advantage — the annual adjustment of rent to inflation.

This measure directly affects thousands of landlords. A poorly insulated property does not only generate high charges for the tenant: it also costs the landlord, who sees their real rent decrease every year relative to inflation.

To manage your EPC obligations and track indexation deadlines, a rental management software centralises all the necessary information.

Ban thresholds by region

Brussels-Capital

In Brussels, the measure is the strictest: all properties rated E, F or G are affected, without distinction. The rules apply to both current and new leases.

Wallonia

Wallonia has opted for a progressive system: properties rated F are subject to a halved indexation, only G properties are fully blocked.

Flanders

Flanders entered the system in 2026, with a system similar to Wallonia. Properties rated E remain unaffected for now.

Concrete financial impact

The indexation ban has a real and growing cost for the landlord. With an average annual inflation of 2 to 3%, a non-indexed rent quickly loses value.

5-year simulation

For a base rent of 900 EUR/month with annual inflation of 2.5%:

Over 5 years, a landlord who cannot index loses more than 4,200 EUR on a single property. For a portfolio of 3 flats, the loss exceeds 12,600 EUR — often more than the cost of an energy renovation.

The combined effect on profitability

The indexation ban is not limited to the direct financial loss. It also affects:

• The property’s resale value: an investor-buyer will calculate their yield on a non-indexable rent
• The property’s attractiveness: a poor EPC attracts less solvent tenants (high energy charges = reduced housing budget)
• Bank financing: some banks take the EPC into account when granting property loans

Solutions to restore the right to index

Priority works

To significantly improve the EPC, focus on the most impactful items:

1. Roof insulation: gain of 1 to 2 EPC classes for 8,000 to 15,000 EUR
2. Window replacement: gain of 0.5 to 1.5 classes for 6,000 to 12,000 EUR
3. Wall insulation: gain of 1 to 2 classes for 10,000 to 20,000 EUR (external)
4. Condensing boiler or heat pump: gain of 0.5 to 1 class for 4,000 to 15,000 EUR

Available grants

Optimal timing

The best time to carry out works is between two leases, during the vacancy period. If the property is occupied, plan the least intrusive works (roof insulation, boiler replacement) and schedule the heavier ones (windows, walls) at the next turnover.

To assess the profitability of renovation, see our article on whether to renovate before letting.

Conclusion: index or renovate — the maths is clear

The EPC-related indexation ban is not merely a regulatory constraint: it is an economic signal. Landlords who invest in energy renovation not only recover the right to index, but also gain in rental and asset value.

Key points to remember:

1. Brussels is the strictest: E, F and G have been blocked since 2023
2. Wallonia and Flanders apply a progressive system (F at 50%, G blocked)
3. The financial loss exceeds 4,000 EUR over 5 years for a single property
4. Regional grants cover 20 to 70% of the cost of works
5. The new EPC immediately restores the right to index

To automatically track your indexation deadlines and EPC obligations for each property, use our rental management platform. Generate your lease agreements with a correctly configured indexation clause.