Introduction to the Swiss mortgage system

Securing a mortgage to buy property in Switzerland is significantly different from many other countries. One of the most notable features of the Swiss real estate market is that homeowners rarely pay off their entire mortgage. Instead, mortgages are designed to be carried long-term, sometimes indefinitely, to optimize tax liability. In Switzerland, debt is treated as a tax-efficient financial instrument because mortgage interest can be deducted directly from your taxable income. For expats settling in Switzerland, understanding this unique structure is the first step toward successful homeownership.

A typical Swiss mortgage is structured in two tiers. The first mortgage (known as the prime mortgage) covers up to 65% or 67% of the property's purchase price. This portion of the loan does not have a mandatory repayment schedule; you only pay the interest. The second mortgage covers the remaining amount up to the maximum loan-to-value (LTV) ratio of 80%. This second mortgage must be amortized (repaid) over a maximum of 15 years, or by the time the borrower reaches the official Swiss retirement age of 65. To evaluate whether buying is the right choice for you, read our detailed buy vs rent analysis.

Eligibility for a mortgage in Switzerland depends on your residency permit and nationality. EU/EFTA nationals holding B or C permits face very few restrictions and are treated similarly to Swiss citizens. However, third-country nationals (such as UK, US, or Indian citizens) holding B permits face stricter guidelines under Lex Koller rules. Non-residents can also obtain Swiss mortgages, but lenders generally demand higher down payments, lower loan-to-value ratios, and charge higher interest rates to offset the perceived risk.

Down payment and equity requirements in 2026

In 2026, Swiss banks strictly enforce down payment rules. To secure a residential mortgage, you must provide a minimum of 20% of the property's purchase price as equity. Lenders will verify the source of these funds to ensure they comply with national regulatory frameworks. Specifically, at least 10% of the purchase price must be provided in 'hard equity' — such as cash savings, liquidated stock portfolios, or interest-free loans from family members.

The remaining 10% of the down payment can be sourced from your Swiss retirement assets. This includes pledging or withdrawing funds from your occupational pension (the second pillar) or your private pension (Pillar 3a). While utilizing pension assets helps expats get onto the property ladder sooner, it has long-term implications. Withdrawing funds reduces your future retirement benefits and triggers immediate taxation, whereas pledging (Verpfändung) leaves the capital intact but increases the interest burden. Make sure you understand the tax impact of these options in our Swiss wealth tax guide.

It is also critical to understand that the property valuation used by the bank (the lending value or Belehnungswert) may not match the actual purchase price. In Switzerland, banks perform independent valuations. If you agree to buy a home for 1,200,000 CHF, but the bank values it at only 1,100,000 CHF, the bank will base its 80% mortgage limit on the lower valuation (880,000 CHF). In this scenario, you must pay the difference of 100,000 CHF out of your own pocket in addition to the standard 20% down payment, raising your total equity requirement significantly.

SARON vs. fixed-rate mortgages in Switzerland

When structuring your Swiss mortgage, the choice of interest rate model is crucial. Borrowers must decide between fixed-rate mortgages and money-market-indexed loans, which are tied to the Swiss Average Rate Overnight (SARON). Fixed-rate mortgages offer complete budget certainty, with terms ranging from 2 to 15 years (and sometimes up to 25 years). During this term, your interest rate and monthly payments remain completely unchanged, shielding you from interest rate increases.

SARON mortgages, on the other hand, fluctuate in line with market rates. The rate is calculated daily based on transactions in the Swiss franc repo market and is heavily influenced by the monetary policy decisions of the Swiss National Bank (SNB). SARON mortgages are structured with a framework agreement, typically lasting 3 to 5 years, during which the lender adds a fixed margin (often between 0.6% and 1.2%) to the daily SARON rate. If the SNB keeps interest rates low, SARON mortgages are usually the cheapest option on the market, but they expose you to immediate rate hikes if monetary policy tightens.

Many Swiss lenders allow borrowers to split their mortgage into multiple tranches. For example, you can place 50% of the loan in a 10-year fixed-rate tranche to secure stability, and the other 50% in a SARON tranche to capitalize on lower variable rates. This strategy reduces the risk of having to refinance your entire mortgage at a high point in the interest rate cycle, which is a common hazard for expat buyers.

The affordability test (Tragbarkeit) explained

Even if you have the required 20% down payment, Swiss banks will not grant a mortgage unless you pass a strict affordability test. This test is designed to ensure that you can continue to pay your mortgage even in a worst-case scenario. Instead of using current interest rates (which might be around 1.5% to 2.5%), banks calculate affordability using a theoretical, long-term 'imputed' interest rate of 5.0% to 5.25%.

Under the affordability formula, the total annual cost of owning the home cannot exceed 33% (one-third) of your gross annual household income. Lenders calculate the total cost by adding: the theoretical interest on the loan (5% of the total mortgage amount), mandatory amortization (typically 1% of the loan amount per year for the second mortgage), and estimated maintenance and utility costs (set at 1% of the property value per year).

For example, if you seek a 800,000 CHF mortgage on a 1,000,000 CHF home, the bank's annual calculation will look like this: 40,000 CHF in theoretical interest (5% of 800k), 10,000 CHF in maintenance (1% of 1M), and roughly 6,700 CHF in amortization. This results in a total theoretical cost of 56,700 CHF per year. To pass the test, your gross household income must be at least 171,800 CHF per year. If your income falls short of this limit, the bank will refuse the loan, even if you can easily afford the actual monthly payments under current market rates.

Tax implications and imputed rental value

Owning a home in Switzerland has unique tax consequences that can surprise expats. On the positive side, you can deduct all mortgage interest payments and direct maintenance expenses from your taxable income on your annual tax return. This makes high mortgages attractive to high-earning individuals who wish to lower their marginal tax rate. Additionally, debt is deducted from your assets when calculating the canton-level wealth tax.

Looking at the other side of the equation, Switzerland balances these tax deductions with a unique tax known as the imputed rental value (Eigenmietwert / Valeur locative). The Swiss government views homeownership as a source of non-cash income. Lenders and cantonal tax offices estimate the amount you would receive if you rented your home to a third party (typically set at 60% to 70% of market value). This estimated amount is added directly to your taxable income every year, raising your income tax liability. This tax makes carrying a mortgage advantageous, as the interest deductions offset the imputed rental income.

The Swiss parliament has recently debated the complete abolition of the imputed rental value. This reform is expected to phase in gradually between 2026 and 2029. Under the proposed change, the Eigenmietwert tax will be eliminated for primary residences, but corresponding mortgage interest deductions will also be severely capped or eliminated. Expats planning long-term property purchases must monitor these legislative changes, as they will alter the mathematical balance of carrying debt versus paying down mortgages.