Is there a cap on rent indexation in Belgium?
Belgian law sets no federal percentage cap, but the limit comes from regional EPC coefficients. Detail by region and by class.
Brief answer
In Belgium, no federal percentage cap frames the indexation of residential rents: the
official formula (Rent × New index ÷ Base index) mechanically follows the Statbel health
index, regardless of its magnitude. The only limits are the regional EPC-related
coefficients: Brussels (leases pre-14/10/2022) and Flanders (all leases) cap at 75 %,
50 % or 0 % depending on the energy class. In Wallonia, the capping window ended on
31 October 2023, but the EPC D to G leases it affected have since been indexed under a
special method rebased on the capped rent.
Effective maximum cap: 0 % indexation for a class F or G dwelling in Brussels (lease pre-2022) and G in Flanders. Calculate the exact cap for your situation via the calculator.
The principle: no federal cap
Belgian federal law — Law of 6 August 1993 on lease contracts and article 1728bis of the Civil Code — imposes no maximum percentage on annual indexation. The formula is neutral:
Indexed rent = Initial rent × (Health index of the month preceding the anniversary ÷ Health index of the month preceding the signature)
If the health index rises 9 % in a year (case of 2022), the rent rises 9 %. If it falls (rare but possible), the rent falls in theory — Belgian case law admits negative indexation, even if in practice it is extremely rare.
For the complete formula and our legal sources, see our methodology.
The real caps: regional EPC coefficients
Where the federal legislator imposed nothing, the three regions have introduced reduction mechanisms that act as a de facto cap on energetically inefficient dwellings.
Brussels: capping only for old leases
| EPC class | Applied coefficient | Effective indexation |
|---|---|---|
| A, B, C | 100 % | Full indexation |
| D, E | 75 % | Three quarters of the increase |
| F, G | 0 % | No indexation possible |
This coefficient (article 224/2 § 1bis/2 of the Brussels Housing Code) only applies to leases signed before 14 October 2022. For more recent leases: full indexation at 100 %, without cap. Detail in our Brussels page.
Flanders: permanent capping for all leases
| EPC class | Applied coefficient | Effective indexation |
|---|---|---|
| A, B | 100 % | Full indexation |
| C | 75 % | Three quarters |
| D, E, F | 50 % | Half only |
| G | 0 % | No indexation possible |
The Flemish decree of 4 July 2023 made this mechanism permanent. It applies to all residential leases in Flanders, regardless of signature date. It is by far the most restrictive regime of the three regions.
Wallonia: end of the window, but permanent special method
Wallonia experienced a capping window between November 2022 and October 2023 (decree of 19 October 2022, still in force). Since 1 November 2023, there is no more multiplying coefficient, but leases rated EPC D to G that had an anniversary during the window are indexed under a permanent special calculation method: the calculation is rebased on the adapted (capped) rent of 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 federal standard formula.
Detail on our Wallonia page.
Recap table of caps by region and class
| Region \ EPC | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|
| Wallonia (2026)¹ | 100 % | 100 % | 100 % | 100 % | 100 % | 100 % | 100 % |
| Brussels (lease < 14/10/2022) | 100 % | 100 % | 100 % | 75 % | 75 % | 0 % | 0 % |
| Brussels (lease ≥ 14/10/2022) | 100 % | 100 % | 100 % | 100 % | 100 % | 100 % | 100 % |
| Flanders (all leases) | 100 % | 100 % | 75 % | 50 % | 50 % | 50 % | 0 % |
¹ No multiplying coefficient in Wallonia, but for D to G leases with an anniversary during the 2022-2023 window, the calculation is rebased on the capped rent of that period (special method — see above): the result remains lower than the standard formula.
Worked examples of the effective cap
For an initial rent of 800 €/month indexed in July 2026 (full theoretical increase ~25 €/month):
| Case | Coefficient | Effective increase | New rent |
|---|---|---|---|
| Wallonia, class G (lease with no anniversary in the 2022-2023 window) | 100 % | +20 € | 820 € |
| Brussels lease 2020, class G | 0 % | 0 € | 800 € (freeze) |
| Brussels lease 2024, class G | 100 % | +20 € | 820 € |
| Flanders, class G | 0 % | 0 € | 800 € (freeze) |
| Flanders, class D | 50 % | +10 € | 810 € |
For your exact situation, the calculator automatically applies the right coefficient.
Why has Belgian law not set a federal cap?
Three historical reasons:
- Contractual balance — indexation is conceived as a simple update of the initial rent in the face of inflation. Setting it at a cap would amount to organising a real loss of value for the landlord, which discourages rental investment.
- Macro-economic logic — the health index already excludes the most volatile components (fuels, tobacco, alcohol). The 1993 legislator considered this weighting sufficient to absorb shocks.
- Regional subsidiarity — since the sixth state reform (2014), the regions are competent in housing matters. They can therefore modulate federal rules through their own mechanisms (e.g. EPC coefficients), making a federal cap redundant.
And exceptional measures (freeze)?
In periods of extreme inflation (>5 % annual), the legislator can intervene punctually to freeze or cap indexation. This happened:
- Wallonia: partial freeze or capping November 2022 → October 2023 (EPC D to G), whose effect remains anchored through the special method of the decree of 19 October 2022
- Brussels: transition to permanent coefficient (cf. supra)
- Flanders: transitional freeze 2022-2023, made permanent in 2023
These measures are always temporary in their principle, but can be extended or made permanent if the economic context justifies it. In 2026, no new freeze measure is in discussion at the federal level, and only the permanent regional measures described above remain.
Special case: negative indexation
Theoretically, if the health index drops between signature and anniversary date (deflation), the formula produces a rent lower than the initial rent. Three case-laws exist:
- Majority school: negative indexation is applicable (the formula is neutral)
- Minority school: indexation is a right, so the landlord can waive an unfavourable result
- Practice: the case is so rare (the last annual health deflation dates to 2009) that it is never decided by the Court of Cassation
In 2026, with positive health inflation for over 15 years, the question remains theoretical.
To go further
- Calculate the indexation and its exact cap — EPC coefficient applied automatically
- Indexation after 5 years — historical cumulation vs annual cap
- Can indexation be refused? — valid grounds related to EPC
- Wallonia indexation — 2022-2023 window and special method
- Brussels indexation — detail of the transitional coefficient
- Flanders indexation — detail of the permanent decree
- When can one index? — annual calendar
- Complete methodology — legal sources and formula
The « cap » is not a legal notion at the federal level. It is, however, an operational reality in Brussels and Flanders — and a durably anchored effect in Wallonia for D to G leases that went through the 2022-2023 window — and it is precisely the dwelling’s energy class that sets the threshold.
Frequently asked questions
Does a legal percentage cap on rent indexation exist in Belgium? + −
No, no federal cap expressed in percentage exists. The Law of 6 August 1993 and article 1728bis of the Civil Code refer to the formula of the health index without imposing an upper limit. If health inflation rises by 9 % in a year, indexation can follow the same increase. The only existing 'caps' are the regional EPC coefficients (Brussels pre-2022, Flanders permanent), which reduce the indexed share for poorly EPC-rated dwellings.
Is the 2022-2023 rent freeze still in force? + −
No, no longer in 2026 — but its effects persist. The partial freeze concerned Wallonia (window Nov 2022 → Oct 2023), Brussels (transitional mechanism made permanent for leases prior to 14/10/2022) and Flanders (transitional freeze made permanent decree of 4 July 2023). Today, Brussels (old leases) and Flanders (all leases) still apply an EPC reduction; in Wallonia, EPC D to G leases indexed during the window follow a permanent special method rebased on the capped rent (decree of 19 October 2022, still in force).
What is the effective maximum indexation for a class G dwelling? + −
It depends on the region and the lease date. In Brussels (lease signed before 14/10/2022) and in Flanders (any lease), a class G dwelling has a coefficient of 0 %: no indexation possible, the rent stays at its initial level. In Wallonia, a G can be indexed again since end of 2023, but if the lease had an anniversary during the 2022-2023 window, the calculation is rebased on the capped rent (special method): its rent remains durably lower than the standard formula. EPC G is therefore the de facto 'cap' in Brussels (old leases) and Flanders.
Can indexation exceed price inflation? + −
Yes theoretically, because the health index excludes fuels and tobacco, and can therefore evolve differently from the general price index. In practice, over the last ten years, the health index closely follows general inflation. In 2022-2023, the health index even slightly slowed inflation (~9 % vs ~10 % on the CPI), which avoided the worst for Belgian tenants.
Can the landlord voluntarily waive applying the cap? + −
The question makes no sense in the common sense: there is no cap to 'lift'. The landlord can either apply the full indexation according to the formula, or waive indexation (totally or partially). Waiving part of the increase is legally possible but must then be clearly notified, as it creates a factual precedent useful to the tenant in case of subsequent dispute.
What happens if inflation explodes again (10-15 % per year)? + −
Without political intervention, indexation mechanically follows the health index, without federal cap. A 15 % inflation would generate a 15 % rent increase in the same year. Historically, it is precisely in these situations that regions intervene with temporary measures (freeze or capping). In 2026, no freeze measure is in force, but the 2022-2023 experience shows that a mechanism can be reactivated within weeks in case of crisis.
Calculate your indexation
Our tool automatically applies the Belgian legal formula with up-to-date Statbel indexes.
Go to the calculator →This article is informational and does not constitute legal advice. For any disputed or complex situation, consult a lawyer or the justice of the peace of the property's commune (free procedure).