Recent case law on rent indexation in Belgium
Key decisions from Belgian justice of the peace courts on rent indexation: EPC and indexation, retroactivity, calculation errors, abusive indexation. 4 rulings analysed.
361days ago
!What changes
- 1The Brussels justice of the peace confirms that indexation without a valid EPC is void (March 2026)
- 2A Liege judge orders repayment of 3 years of indexation calculated on the wrong index
- 3The Constitutional Court validates the Brussels indexation freeze for EPC E-G properties
- 4A Ghent ruling specifies that late indexation (>3 months) is permanently lost
Context: indexation before the courts
Rent indexation is the most common topic before Belgian justice of the peace courts in rental matters. The 2022-2023 inflation crisis multiplied disputes: calculation challenges, indexation without EPC, non-compliance with freezes, abusive retroactivity.
In 2025-2026, several important decisions clarified the applicable law. These rulings set precedents and directly impact the day-to-day practice of landlords. Here are the 4 most significant rulings.
Fundamental reminder: indexation must be requested in writing by the landlord. It can only have retroactive effect for a maximum of 3 months.
Ruling 1: no EPC, no indexation (Brussels, March 2026)
Justice of the peace Brussels-3, 12 March 2026
A Brussels landlord had indexed their tenant’s rent every year since 2020 without ever having obtained an EPC certificate. The tenant challenged this in 2025 and requested reimbursement of indexation collected since November 2022.
Decision: The judge ruled in favour of the tenant. The indexation applied since November 2022 without EPC is void by operation of law. The landlord is ordered to reimburse EUR 2,840 (34 months of indexation at EUR 83.50/month) plus legal interest.
Significance: This ruling confirms that the EPC obligation for indexation is not a formality but a validity condition. Any Brussels landlord who indexes without an EPC faces full reimbursement. Rent indexation must always be preceded by EPC verification.
Ruling 2: wrong base index = reimbursement (Liege, January 2026)
Justice of the peace Liege-1, 22 January 2026
A landlord had used the wrong base index to calculate indexation for 3 years. Instead of the index of the month the lease was signed (September 2019), they had used the January 2019 index. The error, small at first (EUR 2/month), accumulated with inflation.
Decision: The judge orders reimbursement of EUR 1,260 corresponding to 36 months of overpayment, plus EUR 180 in legal interest. The landlord is also ordered to pay costs (EUR 420).
Significance: The base index is that of the month preceding the month the lease was signed (not the month of move-in, not January). A small error compounds year after year and can generate significant reimbursements.
The base index appears on the registered lease. If in doubt, verify on the FPS Economy website (statbel.fgov.be) or use our indexation calculator.
Ruling 3: Constitutional Court validates the Brussels freeze (October 2025)
Constitutional Court, ruling 142/2025, 15 October 2025
Several Brussels landlords challenged the indexation freeze for EPC E-G rated properties (November 2022-October 2023) before the Constitutional Court, invoking an infringement of the right to property.
Decision: The Court dismisses the appeal. The freeze is proportionate and justified by the objective of protecting tenants from exceptional inflation and by the incentive for energy renovation.
Significance: This ruling definitively closes the door to appeals by Brussels landlords. The freeze is final and will not be subject to any compensation. It is also a strong signal: regional legislators can make property rights conditional on EPC without violating the Constitution.
Ruling 4: late indexation = right lost (Ghent, December 2025)
Justice of the peace Ghent-1, 3 December 2025
A Flemish landlord had not indexed the rent for 2 years (oversight). In 2025, they sent a retroactive indexation request covering the 2 missing years.
Decision: The judge confirms that indexation can only be claimed retroactively for a maximum of 3 months. The remaining 21 months are permanently lost. The landlord cannot accumulate unclaimed indexations.
Significance: Indexation is a right that lapses quickly. If the landlord does not claim it within 3 months of the anniversary date, that year’s indexation is lost. No catch-up is possible. A rental management tool with automatic alerts prevents this type of oversight.
Lessons for landlords
These rulings outline a clear framework:
- Obtain the EPC before any indexation (mandatory in Brussels and Wallonia)
- Verify the base index: it appears on the registered lease, use it meticulously
- Index on the anniversary date: beyond 3 months, the right is lost
- Keep proof of notification (registered letter or certified email)
- Never try to catch up on several years: it is legally impossible and exposes you to litigation
To avoid errors, our indexation calculator uses the official indices and the impact of inflation on rents analyses current trends. If in doubt, consult our indexation FAQ.
Frequently asked questions
-
Yes. The tenant can bring the case before the justice of the peace if they consider the indexation abusive (calculation error, absence of EPC, late indexation). The procedure is quick (2-4 months) and inexpensive.
-
Yes. Several recent decisions have ordered landlords to reimburse overpayments from indexation with legal interest. The limitation period is 5 years.
-
No. Since November 2022, indexation in Brussels is conditional on producing a valid EPC certificate. Without EPC, the indexation is void and the landlord must reimburse the amounts collected.
Manage all your leases in one tool
Lease generation, MyRent registration, payment tracking, digital inventory. 14-day free trial, no card required.