What to do if the landlord indexes too much?

What to do when the landlord overindexes

Follow this procedure:

1. Recalculate: use the base rent from the original lease and official Statbel indices
2. Document the error: compare your result with the landlord’s requested amount
3. Write to the landlord: registered mail with your detailed calculation
4. Request correction: future rent at the correct amount
5. Request reimbursement: any overpaid amounts with legal interest
6. Court: Justice of the Peace if the landlord does not comply

How to prove the overcharge

Your written complaint should include:

• A copy of the original lease (showing the base rent)
• The official Statbel health indices (starting and new)
• Your complete calculation following the legal formula
• The landlord’s calculation (as communicated to you)
• The difference between the two amounts
• A request for correction and reimbursement

Recovering overpaid amounts

If you have been overpaying due to incorrect indexation:

• Statute of limitations: you can claim reimbursement for overpayments made within the last 5 years (general civil prescription)
• Interest: legal interest applies from the date of your written request
• Proof: bank statements showing the higher amounts paid
• Court recovery: the Justice of the Peace can order reimbursement with interest and costs

The amounts can be significant — even a small monthly overcharge of 30 EUR represents 360 EUR per year or 1,800 EUR over 5 years.

Regional specifics

Brussels-Capital Region

Under the Ordinance of 27 July 2017, overindexation that ignores EPC restrictions is a particularly strong ground for recovery.

Wallonia

The Decree of 15 March 2018 provides the same recovery rights. The Justice of the Peace of the property location has jurisdiction.

Flanders

The Flemish Housing Rental Decree of 9 November 2018 provides similar protections. Proceedings are conducted in Dutch.