For a short period the EPC directly controlled indexation in Wallonia. Between 1 November 2022 and 31 October 2023, an anti-crisis measure allowed full indexation only for labels A, B and C, cut it to 75% for D and 50% for E, and froze it entirely for F and G (notaire.be, 2022 to 2023). This linked a home's energy performance straight to the landlord's ability to raise the rent.
That mechanism was temporary. Since 1 November 2023 the PEB score has had no impact on the indexation calculation in Wallonia, which reverted to the standard health-index formula (certinergie.be, 2026). In other words, an F-rated and a B-rated property in Wallonia are now indexed by exactly the same formula.
The EPC has not become irrelevant, though. A valid EPC certificate remains a condition for indexing rent in Wallonia: the label no longer changes the amount, but its absence blocks the increase (certinergie.be, 2026). The certificate must also be available and displayed when the property is advertised for rent, so it is part of the letting file regardless of the score.
The counter-intuitive point is that Wallonia has moved in the opposite direction to its neighbours on this. While Wallonia dropped the energy cap, Brussels keeps a correction factor for older leases on E, F and G homes, and Flanders has scheduled tougher rules, with properties rated E or F unable to be indexed from 2028 and unrentable below class D from 2030 (certinergie.be, 2026). So the answer genuinely depends on which region the property is in.
At a glance
| Period or region | Effect of EPC on rent |
|---|---|
| Wallonia, Nov 2022 to Oct 2023 | D at 75%, E at 50%, F and G frozen |
| Wallonia, from 1 Nov 2023 | No effect on the indexation amount |
| Wallonia, any date | Valid EPC required to index at all |
| Brussels | Correction factor on older leases for E, F, G |
| Flanders, from 2028 | E and F cannot be indexed unless improved |
| Flanders, from 2030 | Cannot be rented below class D |