Untermiete in Germany: When You Can Sublet and When the Landlord Can Say No

A tenant in Germany cannot simply hand a room, or the whole flat, over to someone else. Subletting, Untermiete, is controlled by the Bürgerliches Gesetzbuch (BGB), and the rule that matters most is one that a lot of secondary sources get wrong: there is no separate legal right for a landlord to charge a subletting surcharge just because a tenant sublets. What the landlord can do is narrower, and this page works through exactly what that is.

This page covers when a tenant needs the landlord's permission at all, when a tenant can actually demand that permission, the specific grounds a landlord can still refuse on, what a landlord can and cannot ask for in return, the difference between subletting part of a home and subletting all of it, and how the ordinary rules interact with short-term platforms like Airbnb and with municipal Zweckentfremdung rules.

Information last verified on 20 July 2026. This page provides general legal information and does not constitute legal advice in an individual case.

Why permission comes first

§ 540 Abs. 1 BGB starts from a simple default. A tenant is not entitled to hand over use of the rented home to a third party, and in particular is not entitled to sublet it, without the landlord's permission. That default applies whether the tenant wants to sublet a single room to a flatmate, hand the whole flat to a friend for a few months, or list it on a short-term rental platform.

The same section also fixes what happens if the tenant does hand use over to someone else with permission. Under § 540 Abs. 2 BGB, the tenant remains answerable for any fault the third party commits in using the home, in the same way the tenant would be answerable for their own conduct. Bringing in a subtenant does not shift that responsibility away from the original tenant.

The tenant's right to demand consent, for part of the home

Asking permission is one thing. Being entitled to receive it is another, and German law only guarantees the second in a narrower situation than most tenants expect.

§ 553 Abs. 1 BGB gives a tenant a right to demand the landlord's consent, but three conditions have to be met together. The interest in subletting has to be a legitimate one, it has to have arisen after the tenancy agreement was already signed, and it has to concern only part of the home, not all of it. A tenant who wants to sublet a spare room to cover rent during a period abroad, or to accommodate a partner moving in, is the kind of situation this right is built for.

Worked example

A tenant has rented a two room Berlin flat since signing the lease years earlier. A temporary posting abroad comes up partway through the tenancy, something that was not part of the original plan when the lease was signed. Wanting to keep the flat rather than give it up, the tenant asks the landlord for permission to let a friend use the second room while away.

Because the interest in subletting only arose after the lease began, and because only part of the flat is involved, this is exactly the situation § 553 Abs. 1 BGB is written for. Unless one of the specific refusal grounds below applies, the landlord has to consent.

The grounds a landlord can still refuse on

The right to demand consent is not unconditional. § 553 Abs. 1 BGB itself lists the grounds a landlord can rely on to say no even where a legitimate, post-contract interest in a partial sublet exists: an important reason relating to the third party personally, the home becoming overcrowded by adding the extra occupant, or other reasons that genuinely make the arrangement unacceptable to the landlord.

An important reason concerning the third party is a high bar. It generally means something specific and serious about that particular person, not just the landlord's general preference to keep the flat to a single household. Overcrowding is assessed against the size of the home and the number of people who would end up living there. The catch-all third ground covers cases that do not fit neatly into the first two but still make the arrangement genuinely unreasonable for the landlord to accept.

Is there a rent surcharge the landlord can simply charge?

This is where a great deal of secondary commentary gets the law wrong, describing an Untermietzuschlag as though it were an independent right the landlord can invoke whenever a sublet happens. It is not.

§ 553 Abs. 2 BGB only comes into play where the landlord's consent is itself conditional. It says that where handing the home over is only reasonable for the landlord at all if the rent goes up by an appropriate amount, the landlord can make consent depend on the tenant agreeing to that increase. In other words, the increase is tied to the specific circumstance that makes consent otherwise unreasonable for the landlord, commonly a genuine rise in shared costs from an extra occupant, not a free-standing fee for the privilege of subletting.

§ 553 Abs. 3 BGB then closes off any attempt to contract around this. Any agreement that puts the tenant in a worse position than these rules provide is void, however it is worded in the lease.

Subletting part of the home versus subletting all of it

The demand right in § 553 only reaches subletting part of the dwelling. Handing over the entire flat to someone else, so that the original tenant is no longer living there at all, sits outside that provision.

That does not mean subletting the whole flat is automatically forbidden. It still falls under the general permission requirement in § 540 Abs. 1 BGB, and a landlord can consent to it. What changes is that the tenant has no statutory right to force that consent the way § 553 provides for a partial sublet with a genuine post-contract interest behind it. A landlord asked to approve subletting an entire flat has considerably more discretion to say no.

If the landlord refuses without a valid reason

§ 540 Abs. 1 BGB gives the tenant a specific remedy for an unjustified refusal. Where the landlord refuses permission and there is no important reason concerning the third party's person, the tenant can terminate the tenancy early, using an extraordinary termination that nonetheless runs on the ordinary statutory notice period rather than immediately.

This is a narrower tool than an ordinary ending a tenancy notice. It exists specifically to stop a tenant being locked into a lease they no longer want once a reasonable request to sublet has been refused for no good reason, rather than to shorten the notice period itself.

Airbnb and short-term letting: a related but different question

Handing a spare room to a flatmate for months at a time and listing a flat for a rotating stream of tourists on a booking platform are not the same question under German law, even though both start from the same § 540 permission requirement.

The Bundesgerichtshof addressed exactly this line in a decision handed down on 28 January 2026. A Berlin tenant had sublet a flat he rented for 460 euro a month to two subtenants for a combined 1,100 euro, without the landlord's permission, during a period abroad. The court held that a tenant's interest in subletting under § 553 Abs. 1 BGB exists to let the tenant preserve their home during a genuine change in personal circumstances, not to generate a profit margin between what the tenant pays and what a subtenant is charged. Subletting arranged mainly to profit rather than to preserve the tenancy did not count as a legitimate interest, and the unauthorised, unapproved arrangement justified the landlord's termination.

The same underlying question, whether the arrangement is really about preserving the tenant's home or about running a rental business out of it, tends to come up even more sharply with short-term tourist lets through platforms like Airbnb, where the turnover of occupants and the commercial framing point away from ordinary Untermiete altogether. A tenant considering that route should expect a landlord to have a stronger basis to refuse consent, and should expect scrutiny of whether the arrangement is really the kind of interest § 553 protects at all.

Municipal Zweckentfremdung rules can apply on top

Even where a landlord is willing to consent, a separate layer of law can still block a short-term tourist letting. Many German cities and some entire Länder restrict Zweckentfremdung, converting housing to a use other than ordinary residential living, and treat repeated short-term tourist lets as exactly that kind of conversion.

Berlin's Zweckentfremdungsverbot-Gesetz is a widely cited example. It requires the district office's permission before residential space is used for a materially different purpose, tourist accommodation included, and enforcement sits with the local authority rather than with the landlord. Other cities and Länder run comparable schemes with their own registration requirements and their own penalties. A tenant weighing a short-term letting platform needs to check the local rule where the flat is located, separately from anything worked out with the landlord under the BGB.

For the rules on notice periods and ending a tenancy more generally, see ending a tenancy. For the broader picture of German tenancy law, see German tenancy law.