Raising interest rates makes borrowing more expensive, which reduces spending and investment, which cools demand, which brings prices down. It's essentially making money "cost more" to slow its circulation.

Central banks use several tools: policy rate hikes (the main lever — banks pass this on through higher mortgage and loan rates), quantitative tightening (shrinking the money supply by selling bonds), forward guidance (simply signalling that rates will stay high, which alone can dampen behaviour), and reserve requirements (forcing banks to hold more capital, reducing lending capacity).

The key limitation: rate hikes only address demand-side inflation. When inflation is driven by supply shocks — energy prices, supply chains — rate hikes are a blunt instrument that hurts consumers without fixing the root cause. Much of 2021–2022 inflation was supply-driven, which is why hiking was controversial.

The SNB policy rate is currently 0% (as of March 2026), having been cut from 1.75% in a series of reductions through 2024–2025 as inflation fell back to near zero.

The consensus forecast: no rate changes in 2026, with the first potential hike not expected until the second half of 2027 at the earliest. The SNB has been explicit that it wants to avoid negative rates again, so the floor is effectively here.

Switzerland's inflation is forecast at just 0.3% for 2026 and 0.6% for 2027 — well within the SNB's price stability target of 0–2%. This is the key reason rates are expected to stay low: there's simply no inflationary pressure forcing the SNB to act.

The main upside risk: a major geopolitical shock driving energy/commodity inflation (a repeat of 2022), or a global growth surprise that pushes up import prices.

There have been two meaningful modern hiking cycles:

2004–2007 (normalisation from zero): SNB lifted from 0% to 2.75% over 3 years in gradual 0.25% steps. This is the closest historical parallel to where we are now — coming off zero with low inflation.

2022–2023 (post-pandemic shock): The most dramatic cycle. SNB hiked from −0.75% to +1.75% — a total of +2.50% in five consecutive increases over just 14 months, driven by war in Ukraine and energy price inflation. Then cut all the way back to 0% by mid-2025.

Practical recommendation: use +1.00% as your base stress case. The calculator default of +1.50% is a conservatively cautious middle ground — reasonable for planning purposes.

Note: the SNB moves in 0.25% steps per quarter, so a 1.50% total hike takes ~6 quarters (1.5 years) to fully materialise. The stress test models an instant shock, which slightly overstates the real cost — a conservative bias that's appropriate for planning.

Wars and geopolitical shocks can push rates in either direction: upward if they drive energy/commodity inflation (like 2022), or downward/sideways if they create economic slowdown and uncertainty. Switzerland additionally benefits from safe-haven CHF flows that tend to suppress rates.

Arguments for fixing now (long term): rates are near historic lows — you're locking in at a favourable point. The SNB is already at 0%, so there's very limited further downside for SARON. A multi-family rental property benefits especially from predictable costs for cashflow planning. The geopolitical wildcard is asymmetric: upside risk to rates is larger than downside from here.

Arguments for waiting or going shorter: some analysts expect long-term fixed rates to ease slightly by mid-2026. A 5-year fix gives flexibility to reassess when the cycle potentially turns. SARON at ~0.85% is extremely cheap right now.

Bottom line: There's no compelling reason to panic-fix this week, but equally no reason to wait for rates to drop significantly — the SNB is already at zero. A split or ladder strategy removes the timing pressure entirely: you lock in part now and keep part flexible.

Instead of one single mortgage, you divide the loan into tranches — portions with different rate types and terms. This is standard practice in Switzerland and actively encouraged by banks.

A 2-way split might be: 60% in 10-year fixed + 40% SARON. You get stability on the majority with flexibility on the remainder.

A 3-way ladder (e.g. ~1/3 each: SARON + 5yr fixed + 10yr fixed) staggers your renewal dates so you never have to refinance the entire loan at once. You're always negotiating in a different rate environment, which smooths out cycle risk.

A 4-way ladder (SARON + 3yr + 7yr + 12yr) reduces your maximum single renewal exposure to 25% of the loan. The marginal benefit diminishes after 3 tranches, and banks may charge more complexity overhead or offer weaker margins on smaller individual tranches.

Swiss banks typically require a minimum tranche of CHF 100,000–200,000. With CHF 2.3M you have plenty of room for 3–4 tranches comfortably.

More tranches = more diversification in theory, but with diminishing returns in practice:

Going from 2 → 3 tranches reduces your worst-case single renewal exposure from 50% to 33% of the loan — a meaningful jump.

Going from 3 → 4 tranches reduces it from 33% to 25% — still useful but less impactful.

Going from 4 → 5 tranches reduces it from 25% to 20% — increasingly marginal.

Beyond 3–4 tranches you also face: reduced negotiating leverage per tranche (banks give better margins on larger single amounts), more renewal dates to track and manage simultaneously, and potential admin fees from the bank for complexity.

For your CHF 2.3M property a 4-way ladder is genuinely worth considering — roughly CHF 575K per tranche is still large enough for strong negotiating position, and the staggered renewals every 2–3 years give excellent cycle diversification.

The stress test models what happens to your total interest cost if the SNB raises rates by your chosen percentage. The year 5 trigger was chosen because the SNB is currently expected to hold at 0% through 2026–2027, meaning a realistic hiking cycle would only begin to bite meaningfully around 2028–2030 — roughly 3–5 years from now.

It's a simplified shock model — the full stress amount hits instantly at year 5, rather than gradually over 6 quarters as would happen in reality (the SNB moves in 0.25% steps per quarter). This means the stress scenario slightly overstates the cost of variable strategies, which is a conservative and appropriate bias for planning purposes.

The stress test affects only variable/SARON tranches immediately. Fixed tranches are shielded until their expiry date, at which point they renew at the stressed rate. This is exactly why fixed tranches provide protection — and why the ladder strategy performs well under stress: at any given point, only part of the loan is exposed.

10 years is the right choice — and not just by convention. Looking at Swiss rate cycles historically, a full cycle from low rates through a hiking phase and back down has typically taken 8–12 years:

The 2004–2015 cycle (zero → 2.75% → negative) lasted about 11 years. The 2015–2025 cycle (negative → 1.75% → back to 0%) lasted about 10 years. A 10-year calculator horizon therefore captures roughly one full cycle — meaning you see both the pain of a rate hike and the eventual recovery, regardless of where you start.

For a rental property specifically, 10 years is even more appropriate because rental income planning requires predictable cost assumptions over the medium-to-long term, and you can't easily exit the asset to escape a bad rate environment the way an owner-occupier might downsize.

Use 15 years only if you want the most conservative stress picture — the longer horizon amplifies the impact of a rate hike scenario. Use 5 years if you're close to a major life event (retirement, sale) and genuinely won't hold the full 10.

Some Swiss and Liechtenstein banks (LLB, VP Bank, Raiffeisen) offer a product where you invest a monthly amount alongside your mortgage. In return, they discount your mortgage rate — but they retain a percentage of your investment gains as a profit-share fee.

The bank's logic: "You invest with us, we earn management fees and profit share — in exchange, we reduce your borrowing cost."

Whether it's a good deal depends on two numbers: the rate discount (the benefit) vs. the profit share % (the cost). On CHF 2.3M, a 0.25% discount saves CHF 5,750/year — guaranteed. The profit share only kicks in when the investment actually makes money, and grows as your portfolio grows.

Always ask for the exact profit-share contract in writing before committing. This number is often buried in the fine print and is the single most important variable in the deal.

There are three ways to deploy spare monthly cash alongside your mortgage:

Bank investment deal: invest monthly with the bank, get a rate discount, bank takes a % of gains. Best when your net investment return (after bank cut) exceeds your mortgage rate. Returns are market-dependent and not guaranteed.

Direct amortization: pay the monthly amount directly off the loan principal. Your "return" is exactly your mortgage rate — guaranteed, risk-free. Every CHF paid off the loan saves you interest permanently. Best when the mortgage rate is high or the bank's profit-share cut is large.

The crossover rule: if net investment return after bank cut > mortgage rate → invest. If below → amortize. With current rates (~1.80% mortgage) and a typical 5% gross return with 20% bank cut (= 4% net), investing currently wins. But if the bank takes 35%+ of gains, the deal becomes marginal.

Important Swiss constraint: banks typically require mortgages to stay above 65% LTV, and prefer indirect amortization via 3a pension contributions (which are tax-deductible). Check whether direct amortization is permitted in your contract and whether 3a is already being used first.

Because interest saved compounds on itself. Each CHF you pay off the loan permanently reduces the balance on which interest is calculated. The more you've paid off, the larger the balance reduction, and the more interest you save each subsequent year — even with no additional payments.

In the year-by-year table on the Investment Offset page, you can see the "Interest Saved" column growing each year for amortization, while the bank cut column also grows (because the investment portfolio gets larger). The race between these two effects determines which strategy wins at your time horizon.

In the early years of a low-rate environment, investing typically wins because the portfolio compounds faster than the interest saving grows. Over longer horizons or at higher mortgage rates, amortization's guaranteed return becomes increasingly competitive.

The calculator is a planning and comparison tool, not a precise financial model. Key simplifications to be aware of:

Rate stress is a shock, not a ramp: the full stress amount hits instantly at year 5. In reality the SNB hikes in 0.25% steps over multiple quarters, so the real cost would be lower in year 5–6 and only reach full impact in year 7.

Fixed rates renew at stressed level: when a fixed tranche expires, the model assumes it renews at the current stressed rate. In reality you'd have the choice to refinance, switch lender, or choose a different term.

Investment returns are constant: the model assumes the same % return every year. Real portfolios have volatile years — good and bad. In a year with negative returns, the bank takes no profit share, but you also don't gain.

Rates from March 2026 market data (Comparis, UBS, Swiss Life). Your bank's actual quotes will differ based on your LTV, affordability ratio, creditworthiness, and negotiation.

Use the calculator to understand the relative differences between strategies and test your sensitivity to key variables — not to predict exact CHF amounts.

Sources: Comparis, UBS key4, Swiss Life, MoneyPark (March 2026). Liechtenstein banks (LLB, VP Bank) may differ slightly — always get quotes from both sides of the border. Rates shown are for strong creditworthiness and typical LTV. Your rate may be higher depending on your profile.

Edit all rate fields directly in the Mortgage Split calculator to match your actual bank quotes.