If I pay in to 3a pension pillar and withdraw money in the same year to purchase a house, can I benefit from 3a pillar in-payment tax reduction?

I don't think so.
The moment you pay in and avail of the tax benefit, your fund is locked for 03 years i.e. you can't make any withdrawals. If you do so, you will lose the tax benefit. What you can do (I think) is that you can pledge the fund without making a withdrawal. That is an option which could help you retain the tax benefit. Talk to your banker and pension fund team to be certain.

Unlike with pillar 2, there is no lock in period with pillar 3a. However you can only retrieve funds every 5 years and no repayments are possible.
https://www.credit-suisse.com/ch/en/...ng-201905.html


If you are married the rules are for each spouse separately and independently. Be aware that to be able to pay into pillar 3a one must have an income subject to AHV/OASI. If pillar 2 is paid the contributions are capped at CHF 6'826 (adjusted every year), or if no pillar 2 is paid the contribution is capped at 20% of the net income.

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Thank you. This is already helpful, but it doesn't say what happens if pay in and then payout pillar 3a funds in the same year from tax benefit perspective?

As usual deduct from your income. On the other side pay the special pay out tax. The PostFinance has a handy calculator for the latter https://www.postfinance.ch/en/privat...m-payment.html