EPC and rent indexation in Belgium
Since 2022, the EPC certificate (Energy Performance Certificate) plays a key role in rent indexation in the three regions — through a correction factor with no end date in Brussels and Flanders for leases that entered into force before October 2022, and through a special calculation method for certain leases in Wallonia. Here is how, and with which factors per region.
Status by region in 2026
Wallonia: special method for EPC D to G leases
The limitation period (1 November 2022 → 31 October 2023) is over, but the decree of 19 October 2022 remains in force: leases with EPC D to G or no certificate that had an anniversary during that period have been indexed since 1 November 2023 under a special calculation method, until the end of the tenancy — the calculation starts from the rent as adapted during that period, with the health index of the month preceding that anniversary as starting index. Classes A to C and more recent leases follow the ordinary formula at 100%.
Brussels: still active for older leases
The ordinance of 13 October 2022, followed by that of 13 October 2023, set up the current regime: since 14 October 2023, a correction factor applies to leases that entered into force before 14 October 2022 where the property has an EPC E, F or G. The factor depends on the anniversary month of the entry into force: roughly 0.945 to 0.990 for EPC E, 0.891 to 0.980 for EPC F or G. EPC A to D and more recent leases: indexation at 100%. In all cases the lease must be registered and the EPC certificate provided to the tenant.
Flanders: permanent factor
The decree of 3 October 2022 (amended on 7 October 2022 and 21 April 2023) first limited indexation from 1 October 2022 to 30 September 2023 and has provided, since 1 October 2023, for a correction factor with no end date. It only covers contracts that entered into force before 1 October 2022: roughly 0.945 to 0.980 for EPC D, 0.891 to 0.960 for EPC E, F or no EPC. No EPC is required to index, and label G does not exist in Flanders. EPC A+ to C and more recent contracts: 100%.
Comparison of coefficients
Brussels (leases that entered into force before 14/10/2022)
Leases taking effect from 14/10/2022: 100% all classes. A registered lease and a valid EPB certificate provided to the tenant are required to index. Different percentages applied during the 2022-23 window.
Wallonia (special method)
D-G or no-certificate leases with an anniversary in the 11/2022-10/2023 window: indexation computed from the window's adapted rent (decree of 19/10/2022). Other leases: 100%.
Flanders (permanent, decree of 3 October 2022)
Label G does not exist in the Flemish EPC. Contracts taking effect from 1/10/2022: 100% all classes.
In all three tables the date criterion is the lease's entry into force, not its signature. The 2022-2023 percentages (Brussels: EPC E limited to 50% of the indexation, F-G no indexation; Flanders: EPC D limited to half of the increase, E-F no indexation; Wallonia: D 75% of the increase, E 50%, F-G no indexation) only applied during those temporary periods.
How it applies in practice
In Brussels and Flanders, the correction factor does not apply to the increase alone: it multiplies the full result of the ordinary formula. Mathematically:
Indexed rent = (Base rent × New index ÷ Starting index) × Correction factor
with New index = health index of the month preceding the anniversary of the entry into force
Worked example (Brussels lease, rent €850, EPC E, signed on 10 March 2021, entered into force on 1 April 2021, indexation on 1 April 2026):
- Starting index (February 2021, month preceding signature): 110.39; new index (March 2026): 137.78
- Ordinary formula = 850 × 137.78 ÷ 110.39 = €1,060.90
- Final indexed rent = 1,060.90 × 0.965766823 = €1,024.58
With the same lease but EPC G: factor 0.931533646, so final indexed rent = €988.26. With EPC A to D: €1,060.90, with no correction.
Detail pages by region
- EPC and indexation in Wallonia — 2022-2023 period and special method
- EPC and indexation in Brussels — correction factor for EPC E, F and G
- How to find your property's EPC — practical guide
Links to the calculation
- Main calculator — automatically applies the right correction factor
- Wallonia calculator
- Brussels calculator
- Our methodology — detail of sources and calculation
Frequently asked questions
Does the EPC apply to my lease in all regions? + −
Not to every lease. Wallonia: a special calculation method applies to leases with EPC D to G or no certificate that had an anniversary between 1 November 2022 and 31 October 2023. Brussels: a correction factor applies to leases that entered into force before 14 October 2022 with EPC E, F or G. Flanders: a correction factor applies to contracts that entered into force before 1 October 2022 with EPC D, E, F or no EPC (decree of 3 October 2022). All other leases are indexed at 100%.
What are the EPC factors in practice? + −
In Brussels (leases that entered into force before 14 October 2022): EPC A to D: 100%; EPC E: a factor of roughly 0.945 to 0.990; EPC F-G: roughly 0.891 to 0.980. In Flanders (contracts that entered into force before 1 October 2022): EPC A+ to C: 100%; EPC D: roughly 0.945 to 0.980; EPC E, F or no EPC: roughly 0.891 to 0.960. The factor depends on the anniversary month and multiplies the full indexed rent. In Wallonia there is no factor but a special method. The exact value is automatically applied by our calculator.
How can I find my EPC? + −
See our dedicated guide: how to find your property's EPC.
My EPC has expired: what to do? + −
The EPC is valid for 10 years. In Brussels, an EPC certificate provided to the tenant is a condition for indexing (together with registration of the lease): have a new one issued (count €200-400 depending on region and surface). In Flanders, no EPC is required to index, but an expired EPC is treated as no EPC: for a contract that entered into force before 1 October 2022, the E/F factor then applies. In Wallonia, the certificate is not a general condition for indexation.
Does the EPC apply to commercial leases? + −
No. EPC correction factors only concern residential leases. Commercial leases follow different indexation rules.
Why was the EPC chosen as an indexation criterion? + −
Regions introduced these mechanisms in 2022-2023 in the context of the energy crisis and the high inflation of 2022: limiting indexation of energy-inefficient properties incentivises landlords to renovate and protects tenants of energy-wasting homes from disproportionate rent increases.