Switzerland holds a little-known world record: it is one of the countries where households are the most indebted in the world, at around 123% of GDP (end of 2025), ahead of Australia and Canada. An apparent paradox for a country known for being cautious and prosperous. The explanation lies almost entirely in one thing: the mortgage, which works here in a way that is unique in the world. Here is how.
Why the Swiss (almost) never repay
In most countries, repaying your loan as fast as possible is a life goal. In Switzerland it is often the opposite, for a very concrete tax reason: the imputed rental value. An owner who lives in their home must declare a fictitious income (the rent they are deemed to pay themselves), taxed like real income. In return, they deduct mortgage interest and maintenance costs from their taxes. The logical consequence: the larger the debt, the higher the deductible interest, and the lower the tax. Repaying your mortgage therefore means increasing your taxable income. Many households prefer to keep a large debt and invest their savings elsewhere.
The basic rules: 80%, equity, 1st and 2nd rank
Before buying, three principles shape the whole financing:
- 80% financing maximum: the bank lends at most 80% of the property's value. You must therefore provide 20% equity.
- At least 10% hard equity: of that 20%, half must come from savings other than the 2nd pillar (bank account, 3rd pillar, gift). You may use your LPP assets, but not for the entire contribution.
- Two debt ranks: the 1st rank (up to about 66% of value) does not need to be repaid. The 2nd rank (the slice between 66% and 80%) must be amortised within 15 years, or by retirement age.
In other words, the law only requires you to repay part of the debt. Two thirds of the mortgage may, in theory, never be repaid.
Affordability: the famous 5% theoretical rate
To grant a loan, the bank does not use the real market rate but a theoretical interest rate of about 5% (sometimes 4.5%), far higher than current rates. Add about 1% of the value for maintenance, plus the amortisation of the 2nd rank. The golden rule: all these theoretical costs must not exceed one third of the household's gross income.
This is the constraint that stops the most buyers: a property can be affordable at the real rate of 1.5% yet fail the test at the theoretical 5%. This safeguard, inherited from past property crises, protects the system against a rise in rates. You can estimate the tax impact of your property with our rental value calculator.
Direct or indirect amortisation: the 3rd-pillar specificity
When amortisation is required (the 2nd rank), there are two routes:
- Direct amortisation: you repay the bank each year. The debt falls, but so does your deductible interest, so your taxes rise.
- Indirect amortisation: instead of repaying the bank, you pay the amount into a 3rd-pillar account (3a) pledged to the bank. The debt stays the same (so the interest stays deductible), and your 3a contributions are also deductible. The accumulated capital repays the debt later, at the latest at retirement.
Indirect amortisation through the 3rd pillar is a typically Swiss feature: it turns repaying a debt into a tax-efficient pension investment. It is one of the reasons the debt does not shrink.
Fixed rate or SARON
On rates, two main families. The fixed-rate mortgage locks the rate for 2 to 15 years: full budget visibility. The SARON mortgage follows a variable rate indexed to the Swiss money-market reference rate, which replaced LIBOR: potentially cheaper, but fluctuating. In both cases, the mortgage is renewed at maturity, rarely repaid.
What makes the Swiss system unique in the world
Four features make the Swiss mortgage a case apart:
- The full debt is generally never repaid.
- The tax system (imputed rental value plus interest deduction) rewards debt rather than repayment.
- Amortisation often goes through a pension investment (3rd pillar), not a plain repayment.
- Solvency is checked at a high theoretical rate, not the real rate.
This mix explains the world record in household debt, without reflecting fragility: the counterpart of this debt is a considerable stock of property and pension assets.
What is about to change: the end of the imputed rental value
On 28 September 2025, Swiss voters agreed to abolish the imputed rental value (57.7% in favour). It is not expected to take effect before 2028. The change is major: removing the fictitious income also removes the deduction of mortgage interest for the home you live in. Keeping a large debt purely to save tax will then lose its point, and many owners will have an interest in amortising more. This may be the end of the Swiss exception, but not for a few years.
NeoFidu helps you see clearly: impact of the imputed rental value, direct vs indirect amortisation, taxation of your property. Try our rental value calculator or contact us.
Informative article current as of October 2026; it is not personalised financial, mortgage or tax advice. Banking rules stem from the sector's self-regulation and may vary between institutions. Sources: BIS (household debt), Swiss mortgage self-regulation, federal vote of 28 September 2025.