Rent indexation in Flanders
In the Flemish Region, indexation is governed by the decree of 4 July 2023 and is subject to a permanent EPC coefficient — unlike Wallonia, which abandoned its EPC mechanism at the end of 2023.
In short: in Flanders, indexation is annual, on the anniversary date of the lease's entry into force. A permanent EPC coefficient applies: 100% for A-B, 75% for C-D, 50% for E-F, 0% for G. The decree of 4 July 2023 made permanent this initially temporary mechanism.
The Flemish legal framework
Flemish decree of 1 October 2022
Like Wallonia and Brussels, Flanders introduced in 2022 a mechanism to cap indexation for energy-inefficient properties. The decree of 1 October 2022 initially aimed to limit the impact of inflation on tenants of the least energy-performant properties.
Decree of 4 July 2023 (reinforcement)
Unlike Wallonia, which repealed its EPC mechanism in November 2023, Flanders reinforced and made it permanent through the decree of 4 July 2023. The EPC coefficient becomes permanent and durably conditions the right of indexation. It is currently the strictest regime among the three Belgian regions.
The EPC factor in Flanders
Label G does not exist in the Flemish EPC. Contracts from 1/10/2022: 100% all classes.
Note the Flemish specificity: the coefficient for class C or D is 75% (vs 100% for C in Wallonia/Brussels), and class E or F is 50% (vs 75% in Wallonia/Brussels). The Flemish grid is overall more demanding regarding energy performance.
Differences with Wallonia and Brussels
| Aspect | Wallonia | Brussels | Flanders |
|---|---|---|---|
| EPC active in 2026? | No (repealed 31/10/2023) | Yes (pre-2022 leases) | Yes (permanent) |
| Class C coefficient | 100% | 100% | 75% |
| Class E coefficient | 100% (since 2023) | 75% (pre-2022) | 50% |
| Class G coefficient | 100% (since 2023) | 0% (pre-2022) | 0% |
Calculate your Flemish indexation
The calculator below automatically applies the correct EPC coefficient based on the class you indicate. Select 'Vlaanderen' in the region selector, enter the dates and the initial rent, and the result will take into account the Flemish decree of 4 July 2023.
A few details.
The exact result.
Property region, lease dates, initial rent, EPC class. The calculation runs instantly.
Worked example
Flemish lease signed on 1 September 2022, rent €950, EPC E, indexation on 1 September 2026:
Health index August 2022: 122.03 — Health index August 2026 (estimated): 132.38
EPC E coefficient: 0.5 (50%)
Theoretical increase = 950 × (132.38/122.03 − 1) = €80.57
Increase weighted at 50% = €40.28
Indexed rent = 950 + 40.28 = €990.28
For French-speaking owners of a property in Flanders
If you own a property in the Flemish Region but reside in Wallonia or Brussels, several points to keep in mind:
- The lease contract must be drafted in Dutch (the official regional language)
- The indexation notification to the tenant must also be in Dutch
- Lease registration is performed at the registration office of the location of the property (i.e. in Flanders)
- The calculator remains valid: the formula is national; only the EPC coefficient changes
Frequently asked questions — Flanders
Why is the EPC factor permanent in Flanders? + −
The Flemish decree of 4 July 2023 made permanent a mechanism originally introduced as temporary (Flemish decree of 1 October 2022). In Flanders, the EPC remains a permanent determinant of the right to apply indexation.
What is the difference between EPC and PEB? + −
None in substance — only the wording changes. PEB (Performance Énergétique du Bâtiment) in French, EPC (EnergiePrestatieCertificaat) in Dutch. Same A to G classes, same overall methodology.
My Flemish lease dates from 2024 with EPC E: can I apply indexation? + −
Yes, but with a 50% coefficient in Flanders (vs 75% in Wallonia/Brussels for D-E). The Flemish decree is more restrictive on intermediate classes.
I am a French-speaking owner of a property in Flanders — where should I start? + −
The lease contract must be in Dutch (the official regional language). Indexation must also be notified to the tenant in Dutch. However, the calculation remains based on the single Belgian health index — the formula is identical.
Does the calculator work for Flanders? + −
Yes — select 'Vlaanderen' in the region selector. The EPC coefficient is applied automatically according to the energy class.
What if my EPC is no longer up to date? + −
Have a new certificate issued. Validity is 10 years in Flanders. Without a valid EPC, the coefficient is generally treated as 0 — no indexation possible.
Going further
- Main calculator (select Vlaanderen)
- Our calculation methodology
- Health index table
- Compare with Wallonia
- Compare with Brussels
Page updated on 04/05/2026. Sources: Flemish decree of 1 October 2022, Flemish decree of 4 July 2023, Law of 6 August 1993, Statbel. This content is informational and does not constitute legal advice.