Pillar 3a for tax-at-source individuals: tax deduction and refund

1. Can I contribute to Pillar 3a despite tax at source?

Anyone who works in Switzerland and earns OASI-liable income may contribute to Pillar 3a, regardless of whether taxation is ordinary or via tax at source.

This applies in particular to:

• Persons with a B permit in Swiss employment
• Cross-border commuters with Swiss earned income
• Weekly residents without a settlement permit (C)

The annual contributions follow the same statutory limits as for all gainfully employed persons, up to the applicable maximum contribution. Unlike ordinarily taxed persons with a direct tax deduction, tax-at-source individuals must claim the deduction themselves.

2. Tax at source and Pillar 3a: why the deduction is not automatic

For tax-at-source employees, the tax is deducted monthly by the employer. This deduction is based on the tax-at-source rate, which contains only flat-rate deductions; voluntary 3a contributions are not taken into account. The relief through Pillar 3a therefore only takes effect after an application. Your saving is not smaller as a result, it just comes later, via the subsequent assessment.

How high it turns out depends on the marginal tax rate of your canton of residence and can be determined for your own situation with the tax calculator. For a single person with a taxable income of CHF 100'000, the difference is clear:

_{Combined marginal tax rates (federal, cantonal, municipal) at the cantonal capital, single person without church affiliation, as of 2026. Values differ for other municipalities.}

3. Reclaiming the Pillar 3a deduction under tax at source: deadline and process

So that you can deduct the contribution from your taxes, you apply to the cantonal tax office for a subsequent ordinary assessment (NOV). The application must be submitted by 31 March of the following year at the latest. After that, the claim to the tax savings for the relevant tax year lapses.

The process comprises four steps:

1. Make the contribution to Pillar 3a.
2. Have the provider's payment confirmation ready (arrives automatically by post, app or email).
3. Submit the application to the tax office.
4. Await the refund or additional claim.

Example calculation: A 41-year-old project manager from Bern with a B permit and an income of CHF 110'000 paid the maximum contribution of CHF 7'258 into Pillar 3a in 2025. Since she did not apply for a subsequent ordinary assessment, the deduction remained unconsidered for tax purposes. The possible tax savings of around CHF 2'500 lapsed entirely.

4. Tax at source: from what income does a tax return also become mandatory?

From CHF 120'000 gross salary, tax at source alone is no longer enough: additionally, the NOV becomes mandatory, meaning an ordinary tax return. The tax already deducted at source is credited in the process.

The voluntary route has only existed since the 2021 tax-at-source reform; it replaces the former rate correction, through which additional deductions such as Pillar 3a can no longer be claimed. Those who live in Switzerland and apply for the voluntary NOV remain in this procedure until the end of the tax-at-source obligation. Cross-border commuters and other quasi-residents, who tax almost all of their income in Switzerland, can decide anew each year.

Important: The switch does not lower the tax in every case. If the tax rates of the municipality of residence are above the tax-at-source rate, the tax can turn out higher despite the 3a deduction.

More on the NOV

Subsequent ordinary assessment (NOV)

The NOV is the switch from tax at source to ordinary assessment. Compando guides through requirements, deadlines and long-term consequences from CHF 120'000 and with a voluntary application.

5. Conclusion: is Pillar 3a worthwhile under tax at source?

Yes. Even under tax at source, Pillar 3a delivers the full tax advantage. You just have to claim the deduction in time.

Beyond the tax, Pillar 3a brings several advantages:

• Tax saving: Every franc paid in lowers your taxable income as soon as you claim the deduction.
• Tax-free growth: Neither income nor wealth tax burdens the 3a assets; in a securities solution it also grows via the compound interest effect.
• Long-term wealth accumulation: Alongside the tax advantage, with every contribution you build up retirement assets, over the years into a noticeable capital sum.

This article was first published on 13/04/2026