Subletting in Belgium: when is it allowed and how to do it

Subletting in Belgium: the legal principle

Subletting is the operation by which a tenant (the “main tenant”) rents all or part of their property to a third party (the “sub-tenant”). In Belgium, this practice is strictly regulated and, in most cases, prohibited without the landlord’s consent.

With rising rents and the boom in short-term rental platforms, the temptation to sublet is strong. But the legal risks are real and penalties can extend to termination of the lease.

The conditions for lawful subletting

By region

Brussels: partial subletting is authorised if the main tenant maintains their residence in the property and the landlord gives their written consent. Total subletting is prohibited for main residence leases.

Wallonia: same principles. The tenant must maintain their residence in the property. The landlord’s consent is necessary. The lease can explicitly prohibit any subletting.

Flanders: the Woninghuurdecreet provides that subletting is only possible with the landlord’s written consent. The tenant must maintain their residence in the property.

Cumulative conditions

1. Written consent from the landlord: verbal agreement is not sufficient. Obtain a letter or lease amendment.
2. Residence maintained: the main tenant must continue to live in the property.
3. Proportional rent: the sub-rent cannot exceed the corresponding share of the main rent.
4. Written contract: a subletting contract must be drafted between the main tenant and the sub-tenant.
5. Compliance with the main lease: the sub-tenant is bound by the same obligations as the main tenant.

The subletting contract

Essential clauses

The subletting contract must contain:

• The parties: identity of the main tenant and the sub-tenant
• Description of the sublet property: room, part of the property, accessible common areas
• Duration: the subletting cannot exceed the duration of the main lease
• Rent and charges: amount, due date, payment method
• Rental guarantee: amount and terms
• Sub-tenant’s obligations: maintenance, noise, house rules
• Termination conditions: notice period, grounds

The main tenant’s liability

The main tenant remains solely liable to the landlord for the performance of the lease. If the sub-tenant causes damage or fails to pay their share, the main tenant is answerable. The landlord has no contractual relationship with the sub-tenant.

To understand the essential clauses of a lease, consult our dedicated guide.

Subletting and Airbnb: the trap

Why it is risky

Subletting a rented property on Airbnb combines two problems:

1. Unauthorised subletting: termination of the lease at the tenant’s fault
2. Lack of tourist registration: administrative fine

Many tenants think that renting their property for a few weekends a year on Airbnb is harmless. In reality, even a single night constitutes subletting that requires the landlord’s consent.

Concrete cases

• Holiday absence: you leave for 2 weeks and rent on Airbnb. Without the landlord’s consent, this is unauthorised subletting.
• Spare room: you rent the guest room permanently. This is partial subletting requiring written consent.
• Temporary expatriation: you leave for 6 months and sublet the entire property. This is total subletting, prohibited for main residence leases.

For the rules on seasonal rental, consult our complete guide.

Risks and remedies

What the tenant risks

• Lease termination: the landlord can request judicial termination of the lease at the tenant’s exclusive fault
• Damages: the landlord can claim compensation for the prejudice suffered (property damage, disturbance to neighbours)
• Loss of rental guarantee: damage caused by the sub-tenant will be charged to the main tenant
• Administrative fine: if the subletting includes unregistered tourist activity

The landlord’s remedies

1. Formal notice: registered letter requesting immediate cessation of the subletting
2. Legal action: petition to the justice of the peace for lease termination and eviction
3. Bailiff’s report: to prove the subletting (online listings, witness statements, letterboxes)

How to regularise a subletting

If you are already subletting without consent, the best option is to regularise the situation:

• Request written consent from the landlord retroactively
• Draft a compliant subletting contract
• Register the subletting if necessary

To fully understand your rights as a tenant and the limits of those rights, consult our complete guide. And to manage your lease transparently, use the rental management tools from BailBelgique.