Rent Indexation in Belgium
The Calculation Formula
The formula is identical in all three regions:
| Element | Description |
|---|---|
| New rent | Base rent × New index / Starting index |
| Base rent | Initial rent stated in the lease (excluding charges) |
| New index | Health index of the month preceding the anniversary of the lease's entry into force |
| Starting index | Health index of the month preceding the lease signing (Brussels/Wallonia) or entry into force (Flanders) |
The health index is published monthly by Statbel. It excludes alcohol, tobacco, and fuel.
Practical Example
- Base rent: €900
- Signing: 1 March 2023 → starting index (February 2023): 125.60
- Anniversary: 1 March 2024 → new index (February 2024): 129.17
Calculation: 900 × 129.17 / 125.60 = €925.57
Mandatory Conditions
- The lease contains an indexation clause (included by default in standard leases)
- The lease is registered with the FPS Finance
- Indexation is requested in writing to the tenant (not automatic)
- Maximum once per year, on the anniversary date
- No retroactive effect (except for the last 3 months in Brussels/Wallonia)
Regional Specificities
BBrussels
For leases that entered into force from 14 October 2022 onwards: full indexation is allowed regardless of the EPC rating. No correction factor applies.
For leases that entered into force before 14 October 2022 with an EPC E, F or G: a correction factor applies. This factor varies depending on the anniversary month of the lease. Use the official calculator.
Official calculator: Loyers.brussels
WWallonia
Since 1 November 2023, the EPC limitation has been lifted. Full indexation (100%) is allowed for all EPC ratings (A to G).
For leases whose anniversary fell between 1 November 2022 and 31 October 2023, a limitation applied (75% for EPC D, 50% for EPC E, 0% for EPC F/G). The "adapted" rent from that period serves as the base for future indexations.
More info: SPW Logement — Indexation
VFlanders
For leases that entered into force from 1 October 2022 onwards: full indexation without restriction, regardless of EPC.
For leases that entered into force before 1 October 2022 with an EPC D, E or F: a correction factor applies (prevents recovery of lost indexation during the freeze).
Flanders specificity: the starting index is the one from the month preceding the entry into force of the lease (not the signing date).
More info: Woninghuur Vlaanderen — Indexatie
Common Mistakes to Avoid
- Indexing without a registered lease — the indexation is not valid
- Applying retroactively — only the last 3 months can be claimed (Brussels/Wallonia)
- Using the wrong index — it's the health index (not the CPI) of the month PRECEDING the anniversary date
- Ignoring EPC restrictions — for leases from before October 2022, check the applicable correction factor on the regional calculator
Official Links
- Statbel — Monthly health index — Current and historical values
- MyMinfin — Lease registration — Free procedure via MyMinfin
- Bruxelles Logement — Indexation — Brussels rules
- Loyers.brussels — Official Brussels calculator
- SPW Logement — Wallonia — Wallonia rules
- Woninghuur Vlaanderen — Flanders — Flanders rules
Selectio automatically calculates your rent indexation and notifies you on each anniversary date. Discover Selectio →