Pillar 3a retroactive top-up calculator

New since 2025: paying in what you missed

For decades, Pillar 3a had a strict use-it-or-lose-it rule: if you did not pay in during a calendar year, that year's deduction was gone for good. A revision of the ordinance governing Pillar 3a (BVV 3, SR 831.461.3), in force since 1 January 2025, changed that. A new Article 7a allows a retroactive purchase, often called a top-up or "Nachzahlung", into Pillar 3a for contribution gaps from 2025 onward.

The timing matters: because a gap can only be closed in a later year, the first retroactive purchases are possible in 2026, for the gap year 2025. Years before 2025 can never be bought back, no matter how large the gap. The list of years this calculator offers grows automatically as new gap years become purchasable.

Who can use it

The retroactive purchase is tied to earned income, in both directions. The conditions in the ordinance are:

• In the gap year, you had earned income subject to AHV contributions, so you would have been allowed to pay into Pillar 3a that year.
• In the year of the purchase, you again have AHV-liable earned income.
• You have already paid the full ordinary Pillar 3a contribution for the purchase year itself; only then can a retroactive amount be added on top.
• The gap year lies at most ten years back.
• You are still entitled to pay into Pillar 3a in the purchase year at all (at most five years beyond the reference age, and only while you remain gainfully employed) and you have not yet started drawing retirement benefits from Pillar 3a.

How much you can pay in

Your gap for a year is that year's small Pillar 3a maximum minus what you actually paid. The retroactive purchase in any one year is capped at the small Pillar 3a maximum, the limit that applies to employed people with a pension fund. That cap holds even for the self-employed, whose ordinary limit is higher. If you had no pension fund in a gap year, your own maximum for that year may have been lower still (at most 20% of net earned income), which reduces the purchasable gap. A larger total gap can therefore only be closed over several purchase years, one capped amount at a time, and each gap year can be closed by one single purchase only: a partially closed year cannot be topped up later.

The purchased amount is deductible from taxable income in the year of the purchase, just like an ordinary contribution. This calculator applies the current small maximum from the official parameters; the limit that legally applies to a gap year is the one that was in force in that year.

The estimated tax saving is a band, not a promise

A Pillar 3a deduction is worth more the higher your marginal tax rate, and that rate depends on federal, cantonal and communal tax together with your personal deductions. A calculator that does not know your full tax return cannot state your saving as one exact figure. This tool therefore shows an estimated band across typical Swiss rate levels for your income. The decisive figure is only ever the assessment issued by your cantonal tax administration.

Also worth knowing: money paid into Pillar 3a is not tax-free forever. It is taxed once at withdrawal, separately from other income at a reduced rate. Official information on the retroactive purchase is published by the Federal Social Insurance Office (BSV) and the consolidated ordinance text is on Fedlex.