Taxes · September 2026

Withholding tax: deadline and forfeiture, what you can still save

The claim to the 35 percent lapses in two ways: through the passage of time, or through incorrect declaration. Both can be prevented, often even after the fact.

The two ways the claim lapses

You only get withholding tax back if two things are true. First, you must file the claim in time. Second, your declaration must be complete and correct. If either is missing, this is called forfeiture, and the deposit becomes a final tax.

For private individuals, the securities and assets register in the tax return counts as the claim. So you don't fill in a separate application, but the register has to be correct.

The three-year deadline

The claim lapses if you don't assert it within three years of the end of the calendar year in which the income became due. A dividend from 2023 can therefore still be reclaimed until the end of 2026, but one from 2022 no longer can.

You can file the claim at the earliest from 1 January of the following year, in practice with the tax return for that year.

Incorrectly declared: when it gets critical

Anyone who doesn't properly declare income or the related wealth can lose the claim. It depends on the type of error.

Calculation errors and net amounts

If you declared income but got it wrong, say through a typo or by entering the net amount, the tax authority corrects it. That alone doesn't cause forfeiture on the corrected portion.

Income or account forgotten by mistake

Since 2019 a more lenient rule applies than before. Anyone who negligently failed to declare income can generally make up for it until the assessment becomes final. Even in a back-tax procedure, the claim generally survives in cases of negligence.

Deliberately concealed

What you can still do now

1. Check the deadlines for recent years

   Use the calculator above and see which years' claims are still open. For the year that lapses at the end of this year, now is the moment to act.

2. Get your tax statements

   Request the tax statements for the affected years from your bank or broker. They show the gross income and the tax deducted.

3. Compare against what you declared

   Do the amounts in your tax returns match the statements? Is an account, a custody account or an item of income missing?

4. Contact the tax authority

   If there's a gap, contact your canton's tax authority. Ask about the process for a supplementary declaration. They'll tell you whether a correction to your tax return is enough.

5. For older, untaxed income: bring in a professional

   If income went undeclared for a longer period, a penalty-free voluntary disclosure is available under certain conditions. A fiduciary or tax advisor is the best person to clarify whether and how that applies to your case.

So this doesn't happen to you again

Every year, right after year-end, collect the tax statements from all your banks and brokers in one place. Record every account, even small ones. And always declare the gross income. If you file your tax return on time every year, the three-year deadline is never an issue.

The detailed step-by-step guide to reclaiming it is in the article Reclaiming withholding tax. Official information is available from ch.ch and the Federal Tax Administration.