The rent index provides an orientation as to how high the rent may be. You can find out to what extent it is necessary for a rent increase here.
The landlord may increase the rent at the earliest 15 months after the last rent increase or after a tenant has moved in. He cannot make the increase arbitrarily, but he must orientate himself to the local comparative rent. The landlord may only increase the rent within the applicable cap limit. He must justify the rent increase and needs the consent of the tenant.
Qualified rent index as a guideline
The qualified rent index serves as a binding basis for a rent increase. It is a collection of data that provides information about the rents for similarly equipped apartments in a borough or municipality.
Since 2023, cities with more than 50,000 inhabitants have had to create and publish a qualified rent index every two years in accordance with § 558c Para. 4 BGB. This is based on scientific data.
The simple rent index
In contrast to the qualified rent index, a simple rent index is only a simple overview of the local comparative rents. It is usually created by the residents of a city themselves and recognized by an authority.
Justification for the rent increase
The landlord must justify a rent increase. Most of the time he refers to the current rent index after the prices for comparable apartments have generally risen.
If there is no rent index, the landlord must name three comparable apartments for which the rent he wants to charge already applies. An apartment is comparable if it is similar in location, size and furnishings.
Other reasons for the rent increase
Further reasons for a rent increase can be a modernization or an energetic renovation of the building. The landlord can allocate up to eight percent of the costs incurred for the measure to the annual rent of the tenants.
Permissible amount of a rent increase
The landlord may request a new rent increase at the earliest one year after the last rent increase. The rent increase may not come into effect earlier than three months after the announcement. A rent increase is therefore possible every 15 months.
Within three years, the rent increase must not be more than 20 percent compared to the last rent. In metropolitan areas, capping limit regulations apply, according to which rents may not increase by more than 15 percent within three years.
Tenant approval required
In order to increase the rent, the landlord needs the consent of the tenants. In compliance with the upper limits and a period of at least 15 months after the last rent increase, the landlord may, if necessary, sue for the consent of the tenants in court.
The rent increase is only permissible if it is requested by all tenants. The landlord must refer to the qualified rent index or to three comparable apartments.
