Who is who in a sublet
In a sublet (Untermiete), the main tenant (Hauptmieter) rents out to you a room or the whole flat that they rent themselves. If it is only for a limited time — for example while the main tenant is abroad — it is often called Zwischenmiete. Important: the sub-tenant (Untermieter) signs a contract only with the main tenant, not with the owner. The main tenant stays responsible to the landlord for the rent and the flat.
If you want to sublet
- Every sublet needs the landlord’s permission (Untervermietungserlaubnis) — for one room, for the whole flat and even for a few weeks. Ask in writing and give the sub-tenant’s name, the rooms and the period.
- If a legitimate interest arose after you signed your contract (for example a change in your family situation, financial reasons or a temporary job in another city), you can usually demand permission to sublet part of the flat. The landlord may refuse for an important reason — for example because of the sub-tenant as a person or overcrowding.
- If the sublet is only acceptable to the landlord for a higher rent, they can make the permission depend on a reasonable surcharge (Untermietzuschlag). The law sets no fixed amount.
- If the landlord refuses permission without an important reason concerning the sub-tenant, you can terminate your own contract early with the statutory notice period. Get advice from a tenants’ association before you do this.
Subletting without permission is risky: the landlord can issue a warning (Abmahnung) and terminate, in serious cases without notice. In early 2026, the Federal Court of Justice (BGH) ruled that a tenant who sublets to make a profit has no right to permission, and upheld the termination in such a Berlin case. You are also liable for damage your sub-tenant causes.
If you are the sub-tenant: your position
- You pay the rent and the deposit to the main tenant, and all your claims are against them only. Ask to see the landlord’s permission to sublet.
- If the main tenancy ends, the landlord can demand that you leave too — even if your own contract is still running. You may then only have claims against the main tenant.
- If you rent a furnished room in a flat where the main tenant lives, or a place only for temporary use, your protection against termination is much weaker and notice periods can be very short.
- If, on the other hand, you rent a flat of your own or an unfurnished room long-term, you usually have the normal rights of a tenant towards the main tenant.
Rent: rent cap and furnished places
In Berlin, the rent cap (Mietpreisbremse) usually applies to sublets too: according to the Berliner Mieterverein, the BGH confirmed this in 2026. Exceptions are places rented only for temporary use and a furnished room in a flat where the main tenant lives. A reasonable surcharge for furniture is allowed, but it must not be used to get around the cap. The federal government is planning new rules for furnished and short-term rentals, so check the current situation before you sign.
Contract, deposit and Anmeldung
- Sign a written contract: the parties, which rooms you use alone and which you share, the rent and what it includes, the deposit, the term and notice. Add a list of the furniture and photos of the condition.
- The deposit (Kaution) may be at most three months’ net cold rent. Pay by bank transfer rather than cash, or ask for a written receipt.
- The landlord’s confirmation (Wohnungsgeberbestätigung) for registration is issued by whoever actually gives you the place to live — in a sublet, the main tenant. They must give it to you within two weeks of moving in, and you must register within two weeks as well. See our guide to the Anmeldung.
- Issuing such a confirmation for people who do not actually live there is prohibited and can lead to a high fine. Never buy a “registration address”.
Holiday rentals in Berlin
Renting your flat to tourists or for a few nights is not an ordinary sublet. Berlin has a ban on misusing housing (Zweckentfremdungsverbot): for this kind of rental, even of your own main home, you usually need a permit or a registration from the district office (Bezirksamt), and breaches can lead to high fines. You also need your landlord’s permission. Details are on berlin.de.
How to spot scams
- Do not pay rent or a deposit before you have seen the place and signed the contract.
- Be careful if the “owner is abroad” and wants to send the keys by post or through a supposed escrow service after you pay.
- Suspiciously cheap offers in central locations, time pressure and requests to pay through cash-transfer services are typical warning signs.
- Do not send a copy of your passport or other documents before you are sure the offer is real.
- Check that the person really lives in and rents the flat: ask to see their rental contract and the permission to sublet.
Still unsure what suits you better? Read our guide WG room or your own flat. On Flat-Radar, you can create a free housing request: landlords see it, and new matching listings come to your e-mail.