A fixed-term work stay abroad is impending. You want to keep your German rental flat and sublet part of it during that time. So that the relief in costs does not jeopardise your own return plans, permission, actual use and the agreement with the other person must match. This article deals with ordinary residential subletting, not tourist letting or the tax assessment of a stay abroad.
Plan the period from both ends
Our editorial recommendation: start with the expected move-out and the planned return. Note which dates are already fixed and which depend only on a possible project extension. Consider which rooms you actually want to keep and how you intend to use them. A flat that is completely given up should not be labelled a partial sublet by a mere change of designation.
Then check the existing tenancy agreement and any permissions already granted. An earlier consent may have related to specific persons or a specific period. In the case decided by the BGH in 2026, an earlier permission had expired; the later concrete subletting was not permitted. [BGH2026] Do not therefore rely on an old consent automatically covering any extended stay.
Distinguish the entitlement to permission from the permission itself
§ 540 BGB requires the landlord’s permission in principle for the transfer of use to third parties. A granted permission does not remove the tenant’s responsibility for attributable fault of the other person in use as regulated in paragraph 2. [ERLAUBNIS]
§ 553 BGB can give rise to a claim to permission to hand over part of the dwelling where a legitimate interest arises after the contract is concluded. But the provision names limits: important reasons in the other person, excessive occupation or other unreasonableness. Under its conditions, a reasonable rent increase can be made a condition of permission. [TEIL] This does not create a blanket authority to hand over the keys before receiving an answer.
Calculate the cost relief transparently
Compare your own housing-related expenses with the planned income and explain their components. Do not use an invented local comparative rent and do not hide a surplus behind an unitemised lump sum.
On 28 January 2026 the BGH in judgment VIII ZR 228/23 confirmed in principle the reduction of one’s own rental expenses as a legitimate interest, irrespective of economic neediness. Profit-making beyond one’s housing-related expenses is not covered. In the decided case there was therefore no corresponding claim to permission. [BGH2026] The judgment is not a general calculation formula for every furniture allowance: the consideration of additional services remained open in this case. The Senate also did not decide the further question concerning the rent brake.
The request must match the actual plans
Describe to the landlord the planned scope, period and the intended person so concretely that the matter can be assessed. Keep draft, request and response together. If conditions or queries remain open, clarify them before any binding handover. Asserting a legitimate interest and having obtained a concrete permission are different statuses.
If later the person, the room layout or the duration changes, review the existing consent again. If permission is refused, a legal assessment is sensible; this article recommends neither unauthorised subletting nor an automatic termination of your main tenancy agreement.
Example: Six months may become nine
In the fictitious case a household is to work abroad for six months initially. For the partial sublet there is a suitable draft, an intended person and a consent relating to that period. Shortly before departure an extension of the work project is discussed. The additional time is not simply offered as already promised residential time. First the existing permission and a legally appropriate agreement for a changed period are clarified.
Do not leave the return to the last chat
Plan accessibility, reports of repairs, payments and the later handback before departure. This includes the keys and items actually handed over and a realistic approach to a delayed or earlier wish to return. Have the legally appropriate duration and termination checked; a private return flight date does not guarantee an effective limitation of the sublet.
Preparation is successful if you can save costs without promising an unsecured housing perspective. Which permission can be claimed in the individual case and which rights arise from a concrete agreement must be assessed on the basis of the complete documents.