Subletting a room in the flat you rent

Sharing a flat to make the numbers work is completely normal. And when a room falls empty in the flat you rent, the idea of bringing someone in and splitting the cost comes up by itself. The catch is that, if you are the tenant and not the owner, that decision is not yours alone.

Why you cannot do it on your own

A residential tenancy agreement is signed with specific people and for a specific use: for you, and whoever was agreed, to live there. Handing part of the home to someone else in exchange for money is a different thing from what was agreed. That is why the general rule in Spain is that subletting a room requires the landlord's consent, and that this consent should be put in writing.

It is not red tape. The landlord accepted a specific risk with specific people: they know who lives in the home, how many they are and what they committed to. If someone new moves in, the use of the flat changes, so does the wear and tear and, sometimes, even the terms of the insurance or of the building's rules. They have a right to have a say.

It is worth separating two things that often get mixed up. Your partner or a relative moving in with you, without paying you for a room, is living together. Renting out a room to a third party in exchange for rent is subletting. The second one needs permission; in the first case it is still worth telling the landlord, because it saves misunderstandings later on.

What to put in writing if the landlord says yes

A yes over the phone is worth little the day something goes wrong. If there is an agreement, put it down on paper. These are the points that save the most headaches:

• Who answers for the contract. Normally the original tenant stays responsible towards the landlord: they pay the full rent, answer for any damage and remain the point of contact. The person taking the room answers to the tenant, not to the owner.
• What exactly is being handed over. The specific room and the use of shared areas: kitchen, bathroom, living room, terrace, storage room or parking space, if there are any.
• How much is paid and how. The price of the room, the payment date and method and, above all, how electricity, water, gas, internet and shared costs are split. Writing down the criterion (equal shares, by consumption, or included in the price) prevents half of the arguments.
• Deposit and damage. If a deposit is asked of the person moving in, say who holds it and in which cases something is deducted. And make clear that damage to shared areas is dealt with separately from damage to the room.
• Duration and notice. How long the sublet lasts and how much notice each side has to give if they want to end it.
• What happens at the end. A sublet cannot outlast the main tenancy: if the tenant leaves or their contract ends, the room ends with it. Saying so from the start stops anyone feeling misled.
• Living together. Visitors, noise, cleaning, pets, smoking. It looks like the least important part and it is what causes the most conflict.

One practical detail: all three of you should keep a signed copy, landlord included.

If you are the landlord and the request reaches you

You are not obliged to say yes, but there is no need to say no by default either. It is a good chance to know who is going to live in your property, instead of finding out from a neighbour. Before answering, ask for the details of the person who would move in, clarify whether anything in the current contract changes, and put in writing that your permission covers that person and that period. If someone else moves in later, it has to be asked again.

The risks of doing it behind their back

Subletting without permission is a breach of contract, and the consequences are not theoretical: the landlord can ask for the tenancy to end, and then both of you leave, the tenant and the person who moved in. Whoever is in the room is also left in a very fragile position, with nothing signed to back them up. And if serious damage or an insurance problem appears, the argument about who pays can turn very ugly.

There is another, less visible consequence: trust. A landlord who finds out that someone has been living in their property without their knowledge is unlikely to renew the contract or give a good reference.

One last piece of advice

Ask first, not afterwards. An email explaining who would move in, from when and on what terms takes ten minutes, leaves a record of what was discussed and very often gets a yes back. That is the difference between sharing a flat with peace of mind and living with the feeling that it could all end at any moment.