IWU study finds one in three German tenant households overburdened by housing costs, with new leases driving the increase

The scale of the burden

A study by the Institut Wohnen und Umwelt (IWU), commissioned by the German Tenants' Association (Deutscher Mieterbund), finds that around 6.6 million tenant households in Germany are overburdened by housing costs. This represents roughly one in three of the country's nearly 20 million tenant households. The study defines overburdening as spending more than 30 percent of net household income on cold rent and heating costs.

Within this group, around 3.2 million households spend more than 40 percent of their net income on housing, while a further 3.4 million spend between 30 and 40 percent. The study is based on data from the 2022 microcensus, updated to 2024 levels using figures from the Federal Statistical Office.

The federal government must now protect tenants from further burdens.

Low-income households hit hardest

The study highlights the acute pressure on low-income households. 42 percent of all tenant households, or 8.3 million, belong to the lower third of the income distribution, with an average net household income of 1,417 euros per month. For the bottom 10 percent of the income distribution, the average housing cost burden reaches 60 percent.

The Federal Statistical Office, using a stricter threshold, reports a lower figure. Its data shows that 11.2 percent of people in Germany were overburdened by housing costs in 2025, defining overburdening only when a household spends more than 40 percent of its income on housing.

New leases drive costs up sharply

A key driver of the increased burden is the cost of recently signed leases. The study finds that rents in contracts signed from 2020 onwards are, on average, a good fifth higher than in older contracts. The housing cost burden for these households is 33 percent, compared to a lower rate for those who moved in before 2020.

The effect is most pronounced in major cities. In Berlin, rents for post-2020 contracts are 29 percent above the average for all rental contracts. The figure is 26 percent in Munich and 25 percent in Frankfurt. In metropolitan areas, the overall housing cost burden exceeds 30 percent, rising to over 35 percent for new contracts.

Calls for policy intervention

Melanie Weber-Moritz, president of the German Tenants' Association, described the figures as alarming and called for stronger tenant protections. She urged the federal government to enforce planned stricter penalties for rent gouging and to tighten the rent brake (Mietpreisbremse).

The spiral of ever-increasing rents must be stopped. To do this, the federal government must enforce the planned stricter punishment of rent gouging, tighten the rent brake, and punish violations with hefty fines so that tenants are finally protected from illegal rent increases.

The association demands that the rent brake, currently limited to tight housing markets and set to expire in 2029, be made permanent and applied nationwide. It also calls for the stock of social housing to be increased from the current 1.1 million units to at least 2 million by 2030, and for more public housing to establish a permanently price-regulated and affordable segment in the rental market.