Why is lease registration mandatory?
Lease registration is a legal obligation. The landlord must file the lease contract with the FPS Finance within two months of signing. For a primary residence lease, registration is free of charge. Register the contract as soon as it is signed.
For the general framework: indexation pillar guide. For registration: lease registration guide.
Unregistered lease and indexation: the strict rule
No registration = no indexation. An unregistered lease deprives the landlord of the right to index the rent. No rent indexation is possible as long as the contract has not been filed with the FPS Finance. The landlord cannot send a valid indexation request. The starting index and the new index cannot be invoked. There is no retroactivity after regularisation. This rule applies in all three regions.
Indexation of an unregistered lease in Wallonia
In Wallonia, the rule is cumulative with the EPC restrictions. A Walloon landlord without a registered lease faces two prohibitions: no registration means no indexation, and EPC restrictions (F/G = total block). Even an EPC A rating does not allow indexation without registration. No correction factor is applicable. See indexation in Wallonia.
Indexation of an unregistered lease in Brussels
In Brussels, the same principle applies: without registration, no indexation. The Brussels-Capital Region adds its own EPC requirements. A Brussels landlord must cumulatively: register the lease, hold a valid EPC certificate, comply with the correction factor. If any of these conditions is missing, indexation is blocked. See indexation in Brussels.
Other consequences of an unregistered lease
Reduced notice period for the tenant
The tenant may leave without notice or with a symbolic one-month notice, without any compensation.
Unregistered lease and inventory: consequences
An unregistered lease with no attached or registered inventory of fixtures will be harder to invoke in the event of a dispute over rental damage. See inventory of fixtures guide.
Unregistered lease and rental deposit: points of attention
The deposit remains valid in principle, but in the event of a dispute over its release, the absence of registration weakens the landlord’s position. See rental deposit guide.
Impact on energy performance
The energy performance of the dwelling does not exempt the landlord from registering. A valid EPC never compensates for the absence of registration.
How to regularise an unregistered lease
The landlord can register the lease at any time, even after several years.
- Gather the original signed contract (date of entry into force).
- Attach the inventory of fixtures if available.
- File via MyRent or MyMinfin, or at the registration office.
- Keep the acknowledgement of receipt.
Filing remains free for a primary residence lease. The landlord regains the right to index — but without retroactive effect. The right to index is fully reactivated for the future. In case of prolonged non-registration, the FPS Finance may apply penalties.
How to register a lease — Register online — Consequences of non-registration — Indexation calculator — Tenant verification.
Frequently asked questions
Unregistered for 3 years?
No retroactive catch-up. Future indexation only after regularisation.
Can the tenant register?
Yes. Free of charge. It activates all legal protections.
10-year unregistered lease = void?
No. Valid between the parties. But loss of rights (indexation, long notice period).
Landlord tries to index an unregistered lease?
Refuse in writing. Lease registration is a prerequisite for any indexation request.
Free registration in 2026?
Yes for primary residences. 0.2% for other residential leases.