What the “Law for the new regulation of statutory regulations on rent limitation” contains

Five-year freeze: Rents for non-price-based apartments are frozen for five years. An inflation adjustment of 1.3 percent per year is planned from 2022.
Retrospective application: The law applies retrospectively as of June 18, 2019, the date on which the cornerstones were passed in the Senate.
First letting in new buildings not affected: First letting in new apartments that were ready for occupancy from 1.1.2014 are exempt from the Berlin Rent Act.
Rent ceilings: In order to set the rent ceilings, the rents of the Berlin rent index 2013 were updated with the real wage development until 2019. The rent limits result from the table of the law and are staggered according to the building age classes and equipment.

Rent ceilings and allowable surcharges

The rent table specifies how high the net rent, depending on the age and equipment of an apartment, can be when re-rented. The upper limit for a modernization can increase by a maximum of 1 € / m² (see modernization). When lowering excessive rents in existing tenancies, the housing-related discounts or surcharges and a flat-rate surcharge of 20% must be taken into account.

First-time occupancy, equipment & rental price per sqm
until 1918 with collective heating and with a bathroom € 6.45
until 1918 with collective heating or with bath € 5.00
until 1918 without central heating and without bathroom € 3.92
1919 to 1949 with collective heating and bathroom € 6.27
1919 to 1949 with collective heating or with bathroom € 5.22
1919 to 1949 without collective heating and without bathroom € 4.59
1950 to 1964 with collective heating and with bathroom € 6.08
1950 to 1964 with collective heating or with bathroom € 5.62
1965 to 1972 with collective heating and bathroom € 5.95
1973 to 1990 with collective heating and with bathroom € 6.04
1991 to 2002 with collective heating and with bathroom € 8.13
2003 to 2013 with collective heating and bathroom € 9.80

For apartments with modern equipment, the value increases by € 1.00. Modern equipment is available if at least three of the following features are present:
elevator accessible without thresholds,
Equipped kitchen,
high quality sanitary equipment,
high quality flooring in the majority of living spaces,
Energy consumption value of less than 120 kWh / (m² a)

How exactly is the rent limit calculated when re-letting?

Apartment in an apartment building:
Table value according to age of construction + 1 € for modern equipment if necessary + modernization if necessary = upper rent limit

Apartment in a 1/2-family house:
Table value according to building age + 10% allowance + possibly 1 € for modern equipment + modernization if necessary = upper rent limit

Berliner Mietendeckel-Rechner

Re-letting: In the case of new letting in the portfolio, the amount of the previous contract rent and the rent limit must not be exceeded. If the previous rent was higher than the upper rent limit, the maximum rent may be rented. If the rent of a modernly furnished apartment is particularly low (less than EUR 5.02 / sqm), it can be increased by a maximum of EUR 1 / sqm to a maximum of EUR 5.02 / sqm if it is re-let.
Existing rents: Only the rent that has been effectively agreed by June 18, 2019 may be claimed. Subsequent seasons and index increases are ineffective. If the apartment was not rented on the cut-off date, only the rent owed last, i.e. the previous rent, may be requested.
First-time rental: If the living space is rented for the first time after the cut-off date or if it is rented out again after the entry into force of this law, a rent in the amount of the upper rent limit may be requested. A first-time letting exists if rooms have previously been rented as commercial premises or if the same rental property is no longer rented, for example because the size of the apartment has changed significantly.
Modernization: Modernization measures (energy renovation, accessibility) are notifiable, surcharges are permitted up to 1 euro per square meter. Support programs are to be used for additional modernization costs. A allocation of costs to the tenant is then not permitted.
Rent reductions: In existing tenancies, tenants should be able to reduce their rent upon request if this is more than 20 percent above the permissible rent limit. Surcharges and discounts for simple location (-28 cents / square meter), medium location (-9 ct / sqm) and good location (+74 ct / sqm) are taken into account. The regulations will only be applied 9 months after the law comes into force.
Hardship cases for landlords: In the case of economic hardship, rent increases should be approved if this is absolutely necessary to avoid the risk to the substance and losses. The approved rent increases above the rent limits are to be cushioned by a rent subsidy from households entitled to the WBS. The rent allowance may not exceed the amount exceeding the rent limit.
Fines: Violations of the requirements of the Berlin Rent Act are considered an administrative offense with a fine of up to 500,000 euros.