The housing cost overburden rate is defined as the percentage of the population living in households where total housing costs represent more than 40% of disposable income (both 'net' of housing allowances).

After SNB interest rate decision - One in five could lose their house
Mortgages are becoming more expensive, while house prices are falling for the first time in years. Hundreds of thousands now have to tremble for their homes.

Homeowners are more comfortable than tenants: they don't have to worry about being evicted for their own use, they can decide for themselves the color of the tiles in the bathroom and, on top of that, they live more cheaply. This logic was valid for a long time - and is now faltering.

Since the Swiss National Bank (SNB) surprisingly raised the key interest rate from minus 0.75 to minus 0.25 percentage points on Thursday, many homeowners have had to tremble for their homes. Mortgage interest rates had already risen over the past few months. Now the rise in interest rates on mortgages is getting a boost.

Fixed-rate mortgages have long climbed above the three percent mark. Many homeowners have therefore recently taken out short-term Saron mortgages. These are variable mortgages with short terms . The Saron is recalculated every day, so the key interest rate decision by the SNB also has an impact accordingly.

At the moment the Saron is still below one percent. But because it is closely based on the key interest rate, an interest rate jump of half a percentage point is now pending. And the end of the road is far from being reached, real estate expert Donato Scognamiglio (52) from the consulting firm Iazi warns in the "Sonntagszeitung": "The supposed security of all those who have fled from fixed to short-term mortgages could turn out to be a risk. Many homeowners will have a problem."

The SNB is likely to raise the key interest rate again in September - SNB President Thomas Jordan (59) indicated this this week. This could also increase the interest rates for Saron mortgages to three percent and more.

In its financial stability report, the SNB calculates that with a mortgage interest rate of three percent, 20 percent of homeowners will no longer meet their bank's affordability rules. With a home ownership rate of around 40 percent, this affects more than 600,000 people!

With interest rates rising, housing costs suddenly exceed a third of their income. Anyone who obediently continues to pay their mortgage debts is under observation by the bank, but need not immediately fear for their home. However, anyone who defaults on payments is in bad shape. In the worst case, there is a risk of losing your home.

In addition to interest rates, homeowners are also concerned about the price level. Because while there was only one direction for real estate for years (upwards), this trend has recently turned into the opposite.

However, it will not only be uncomfortable for homeowners – but ultimately also for tenants. They hardly benefit from the falling prices on the real estate market. On the contrary: in the longer term, the higher key interest rate will also lead to an increase in the reference interest rate – and thus to higher rents. It will probably take another two to three years before that happens.