Berlin landlord refunds tenant €10.000 under rent brake law

A Berlin landlord has refunded his tenant 10.000 euros after she challenged her illegally high rent. The CEO of the rent-reduction service, Conny, says that while it sounds extreme, overpaid rent can quickly add up to such a high amount.

Berlin tenant has rent reduced from €1.090 to €650

Speaking to Berliner Morgenpost, local Stephanie Wollenhaupt explained that in December 2023, she urgently needed to find somewhere in the capital for her and her nine-year-old son to live. The supermarket assistant found a 70-square-metre Altbau flat for 1.090 euros per month.

“[I thought], that’s far too much,” Wollenhaupt told the local newspaper. But she decided to sign the rental contract because she had found no other option.

In early 2024, Wollenhaupt decided to use Conny. The online service checks rental contracts to assess whether a tenant is overpaying under Germany's rent brake law. “My private landlord obviously wanted to scare me off. He stood in front of my door and threatened eviction for personal use (Eigenbedarfskündigung). 

She heard nothing from Conny, and meanwhile her landlord’s lawyer sent letters threatening eviction, and the landlord forbade her from using the front garden. She didn’t know it at the time, but Wollenhaupt had special protection against eviction since her son had been diagnosed with ADHD.

Then, in August 2025, the landlord sent a letter announcing her rent would be reduced from 1.090 euros to 650 euros per month, a 440-euro reduction. He refunded the 8.300 euros in rent she had overpaid since moving in, plus the money she had overpaid on her deposit, bringing the total refund to 10.000 euros.

10.000-euro refunds are not an extreme case

Speaking to Berliner Morgenpost, Conny CEO Daniel Halmer explained that while Wollenhaupt’s case sounds extreme, such refunds are more common than many people might expect.

“It is the logical consequence when landlords have been able to charge rents above the rent cap for years without interference, because nobody enforces it,” Halmer explained. “It is not the tenants who are the exception in standing up for themselves; it is the landlords who abide by the law.”

Germany’s rent brake law, which regulates how much landlords can charge tenants in areas where the rental market is under pressure, currently applies in all 12 Berlin districts and in over 400 local districts across the country.

In Pankow alone, the district where Wollenhaupt and her son live, Conny has found 1.160 cases of landlords charging tenants over the limit set by the local rent index. According to Halmer, tenants in the northeastern district are overcharged an average of 342,52 euros per month.

It’s a similar picture across Berlin’s 11 other districts. According to the Berlin Tenants’ Association, landlords were overcharging rent in 95 percent of the 330 rental contracts it recently assessed.

If you think you are paying too much rent, alongside Conny and the Berlin Tenants’ Association, you can contact Berlin’s Rent Review Office (Mietpreisprüfstelle) for information and advice about how to enforce your right to a rent reduction.