Free calculator

Rent indexation calculator (Belgium)

Work out your legal rent increase using the official Belgian health index — free, no account needed, with a ready-to-send letter to your tenant.

Belgium
Printed on your lease agreement, next to the rent amount.
Leave blank to use the official figure automatically, where available.

This calculator is informational only and not legal advice. It applies the standard Belgian health-index formula; it does not yet account for Brussels' EPC-related corrections or contract-specific clauses. Always check your lease and, if in doubt, a professional.

Let PropertyOS send this automatically, every year

PropertyOS tracks every lease's indexation date, looks up the official index, and reminds you (or sends the letter) automatically — for free, in beta.

Frequently asked questions

The health index is the Belgian consumer price index excluding tobacco, alcohol and fuel, published monthly by Statbel. Most Belgian residential leases use it to adjust rent once a year.

At most once a year, on the anniversary of the lease's start date — never earlier.

In most cases you can claim missed indexation retroactively for up to one year. Confirm the details for your specific situation with a professional.

The formula is the same in Flanders, Brussels and Wallonia. Note that Brussels applies an additional EPC-related correction in some cases, which this calculator does not compute yet.