Saving taxes or building capital — a pension fund buy-in (PK buy-in) can do both. But it's not always the best choice. This article explains when a buy-in truly pays off, when it doesn't, and why opportunity costs are often overlooked. Want the numbers straight away? Our pension fund buy-in calculator works out your effective tax saving and the optimal staggering for your municipality.
What is a pension fund (PK) buy-in?
A pension fund buy-in is a voluntary contribution into Switzerland's 2nd pillar (occupational pension system). It helps you close pension gaps that may have arisen through:
- Part-time work
- Time abroad
- Divorce
- Career changes or other employment interruptions
What is the goal of a PK buy-in?
Most people buy in to reduce their taxes or invest surplus liquidity. But be cautious: a buy-in only makes sense if you also have an exit strategy — meaning you know how and when you'll withdraw the funds.
When does a PK buy-in NOT make sense?
A buy-in is not advisable if, in the same year, you:
- have major property maintenance or renovation costs,
- plan to use pension funds for home ownership (WEF withdrawal), or
- will need the capital in the short term.
When is a PK buy-in worthwhile?
A buy-in is most beneficial:
- in the years before retirement,
- when no WEF (home ownership) withdrawals are planned, and
- if no capital withdrawal is planned within three years of the buy-in.
The opportunity costs of a PK buy-in
Pension fund returns are often modest, especially in the extra-mandatory portion. While diversified equity strategies can yield 5–8% per year, pension funds often generate only 1–2% interest. Over time, that difference compounds — despite short-term tax benefits.
A buy-in can still be worthwhile when paid into a 1e pension plan (allowing higher equity exposure), a few years before retirement, or for highly risk-averse individuals.
Strategy over impulse
A pension fund buy-in isn't a one-size-fits-all solution. It can lower taxes and strengthen your retirement savings — but only when the timing, amount and objective fit your broader financial plan. Explore how buy-ins work alongside your retirement planning strategy. With mortgage-interest deductions shrinking from 2029, a buy-in is also worth weighing against amortisation — see our 2029 homeowner tax guide. Request a personalised assessment or get an instant tax return quote below.
Numbers beat guesswork: our pension fund buy-in calculator shows your effective tax saving, the optimal staggering over several years and the comparison with a 1e plan — in just a few seconds.