The voluntary tax return in Zurich: a decision you can't undo

For B permit holders under CHF 120,000 · Tax year 2025 · Updated July 2026

If you are taxed at source and earn under CHF 120,000, Switzerland gives you a choice most countries don't: you can simply never file a tax return. Or you can raise your hand, file voluntarily, and often get money back every year. The catch is that raising your hand once means raising it forever. This guide explains both sides of that trade before you sign anything.

What filing voluntarily gets you

Your monthly tax deduction is based on an average person. File a return, and the tax office recalculates using your real life instead. Everything personal that the tariff ignores now counts:

• Pillar 3a deposits, up to CHF 7,258 for 2025
• Commuting costs, capped at CHF 5,200 cantonally and CHF 3,300 federally
• Job related education, up to CHF 12,400 cantonally
• Donations to Swiss charities of CHF 100 or more

For someone with a full 3a and a yearly transit pass, the refund is typically in the range of several hundred to over two thousand francs, depending on income and commune. Details and all caps are in our deductions guide.

What it costs you: the lock-in

The request for ordinary assessment (NOV) is a one-way door, and the rules are explicit about it. A validly filed request cannot be withdrawn. And from then on, the tax office assesses you the ordinary way every year automatically, for as long as you remain taxed at source. There is no going back to "just the tariff" after a year where filing happens to suit you.

Why filing can actually lose you money

Here is the part most blog posts skip. The withholding tariff is a canton-wide average, but the ordinary assessment uses your commune's actual multiplier, and Zurich communes differ enormously: Kilchberg applies 72 percent, the city of Zurich 119, Winterthur 125. Live in a high multiplier commune with few deductions, and the ordinary assessment can produce a higher bill than the tariff took. Permanently, every year, because of the lock-in.

The deadline is a forfeit deadline

The signed request must reach the tax office by March 31 of the year after the tax year. For tax year 2026 that is 31 March 2027. Married couples sign together. Miss the date and that year is closed: the withheld tax is final. This is not the deadline you may have heard can be pushed back. Extensions are granted by your commune for filing a tax return; this request is fixed by law and nobody can move it. The next chance is the next tax year.

How to decide

1. Add up your personal deductions for the year: 3a, commute, education, donations.
2. Look up your commune's multiplier. Below roughly 100, the odds favour filing. Well above it, be careful.
3. Compare the tax the ordinary assessment would produce against what was actually withheld. That difference, projected over several years, is the real decision.
4. If the answer is clearly positive, file before the deadline (31 March 2027 for tax year 2026). If it is small or negative, keep the option for a year when your deductions grow.