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 — permanently in Brussels and Flanders, and through a special calculation method for certain leases in Wallonia. Here is how, and with which exact coefficients per region.
Status by region in 2026
Wallonia: special method for EPC D to G leases
The capping window (1 November 2022 → 31 October 2023) is over, but the decree of 19 October 2022 remains in force: leases rated EPC D to G that had an anniversary during that window have since been indexed under a permanent special calculation method — the calculation is rebased on the adapted (capped) rent of the window, with the health index of the month preceding that anniversary as starting index. Classes A to C and more recent leases follow the federal standard formula.
Brussels: still active for older leases
The ordinance of 11 October 2022 introduced an EPC corrective coefficient that applies to leases signed before 14 October 2022. For more recent leases: federal standard calculation (EPC has no impact). The Brussels mechanism is degressive: the coefficient varies depending on the lease's anniversary month.
Flanders: permanent factor
With the decree of 4 July 2023, Flanders made permanent its initially temporary EPC mechanism (decree of 1 October 2022). The coefficient now applies to all leases, regardless of their signature date, and definitively (no end date planned). It is the strictest grid of the three regions.
Comparison of coefficients
Brussels (leases pre-14/10/2022)
Leases signed from 14/10/2022: 100% all classes. A valid EPC certificate provided to the tenant is required to index. Different percentages applied during the 2022-23 window.
Wallonia (historical 2022-2023)
D-G 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 4 July 2023)
Label G does not exist in the Flemish EPC. Contracts from 1/10/2022: 100% all classes.
How it applies in practice
The EPC coefficient does not apply to the total rent but only to the theoretical increase linked to indexation. Mathematically:
Indexed rent = Base rent + (Theoretical increase × EPC coefficient)
with Theoretical increase = Base rent × (New index ÷ Base index − 1)
Worked example (Brussels lease pre-2022, rent €850, EPC E, theoretical increase of €167):
- EPC E coefficient in Brussels: 75 %
- Weighted increase = €167 × 0.75 = €125.25
- Final indexed rent = 850 + 125.25 = €975.25
With the same lease but EPC G: coefficient 0 %, so final indexed rent = €850 (no indexation possible).
Detail pages by region
- EPC and indexation in Wallonia — 2022-2023 window and permanent special method
- EPC and indexation in Brussels — still active rules
- How to find your property's EPC — practical guide
Links to the calculation
- Main calculator — automatically applies the right coefficient
- Wallonia calculator
- Brussels calculator
- Our methodology — detail of sources and calculation
Frequently asked questions
Does the EPC apply to my lease in all regions? + −
No. Wallonia: the capping window ended on 31 October 2023, but a permanent special calculation method still applies to EPC D to G leases indexed during that window. Brussels: yes for leases signed before 14 October 2022. Flanders: yes permanently since the decree of 4 July 2023.
What are the EPC coefficients in practice? + −
Schematically: A-C: 100 % indexation possible, D-E: 75 % (Wal/Bxl) or 50-75 % (Vla), F-G: 0 %. The month-by-month detail 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. If expired, you must have a new one issued (count €200-400 depending on region and surface). Without a valid EPC, indexation of pre-2022 leases (Bxl) or post-2022 leases (Vla) is 0 %.
Does the EPC apply to commercial leases? + −
No. EPC coefficients 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 post-Covid inflation: limiting indexation of energy-inefficient properties incentivises landlords to renovate and protects tenants of energy-wasting homes from disproportionate rent increases.