The attempt went completely wrong: a landlord in Halle an der Saale wanted to use the replacement of smoke detectors as an opportunity to impose a significant rent increase. The tenants defended themselves and finally won justice before the Federal Court of Justice in May 2023: According to the highest court ruling, simply replacing smoke alarms does not justify a rent increase. Because a new smoke detector is usually not a modernization measure, as the owner argued. Only technical improvements or other demonstrable upgrades to a property allow higher rents – for example if the landlord improves energy efficiency. The BGH judges did not see such a situation in the specific case.
The example shows that tenants do not have to accept every increase – and nor should they. “The legal provisions for rent increases are fundamentally clearly regulated,” explains lawyer Florian Timmer on the online portal Rechtsanwalt.de: “Landlords do not have the free hand to increase the rent arbitrarily and to an exorbitant amount.” Rather, every rent increase must be plausibly justified by the landlord, otherwise “an increase in rent is not legal,” says the lawyer. There are strict regulations that must be adhered to in all of this, as the law protects tenants in a special way. In addition to the specific justification, the landlord must also specifically quantify the planned rent increase; he must state the old and new rent. And the tenant pays them no earlier than three months after receiving the rent increase letter.
The following also applies: The first rent increase may not occur until twelve months after moving in. Thereafter, a further waiting period of 15 months applies before a further rent increase is possible. Landlords must also adhere to the so-called capping limit when rent increases. This states: The rent may increase by a maximum of 20 percent within three years. The net rent is decisive for this. In particularly tight housing markets, where the rent cap is in effect, only a 15 percent increase is allowed in three years.
So much for the theory. In practice, however, it appears that landlords have a number of options to circumvent the regulations. For example, a landlord can increase the rent in order to adjust it to the local comparative rent according to the rent index. Some modernization measures can also be passed on to tenants if – as mentioned – they lead to a demonstrable improvement in the value of the apartment or house. A surcharge of up to eight percent of the investment costs is then possible, of course calculated based on the apartment’s share of the house. However, the additional costs required may not add up to more than three euros per square meter. Important to know: In both cases, landlords do not have to adhere to the 15-month waiting period, but can increase the rent earlier.
Another option that landlords like to use to implement rent increases quickly and flexibly are explicit agreements in the rental agreement, i.e. a graduated or so-called index rent. This means that the rent then increases at fixed intervals or adapts to the general rate of inflation.
When it comes to new rentals, landlords can also turn up the price screw. A surcharge of up to 10 percent over the usual comparative rent is permitted here, provided that a rent index exists. If not, the rent may even be up to 20 percent above the general level. If the housing market is very tight, as in Berlin for example, a 10 to 15 percent premium on the current average is still possible for new rentals.
However, resourceful landlords have found a way to get around this brake by offering temporary furnished living space. Such properties are exempt from the rent cap. The same applies to furnished living space in new buildings.
There are always cases in which rent increases are not legal, but landlords still try to enforce them. For example, when changing landlords. Unlike a change of tenant, this alone does not justify a rent increase. The same applies to fake modernization measures such as replacing a doorbell or sign – or a new coat of paint. A retroactive rent increase is also not permitted, as the tenant must always agree to this in advance. As long as consent is missing, a rent increase may not take effect.
Anyone who has doubts about the legality of a rent increase should take the time to check it, if necessary with legal help. A tenant has a total of two months to object to an announced rent increase. He must justify the objection sufficiently and, ideally, in writing. If successful, he saves money – if the increase is legal, you at least gain experience.
This article first appeared in the business magazine “Capital”, which, like stern, is part of RTL Deutschland.