The Risks of Subletting

Subletting your apartment (e.g., putting a room on Airbnb while you travel) is illegal without written authorization from your landlord. If caught, this is grounds for immediate eviction.

Furthermore, income from subletting must be declared to Finanças. If you are a tenant, you cannot charge more rent to a sub-tenant than what you pay proportionally to the landlord (plus a max 20% margin for furniture).