Swiss tax calculator 2025: what six inputs show, and what they miss

The TaxWize tax comparison takes six inputs and estimates what a household pays in tax on its income for tax year 2025: canton, municipality, gross salary, marital status, number of children and church membership. It covers every municipality in the cantons of Aargau, Zurich, Lucerne, Solothurn, Bern, Zug and Schwyz, and it needs neither an account nor a document.

What comes out is an estimate based on the statutory flat-rate deductions. For an employed household that rents and has no sizeable wealth, it usually sits above the tax that's left after a complete tax return. The order of the municipalities usually holds anyway. I built the calculator to guess high when in doubt, and this is where exactly it does.

The number on the phone

Ring a painter and ask what three rooms will cost, and you'll get a number. He knows the square metres and his hourly rate. He doesn't know about the cracks behind the wardrobe, or the ceiling you might paint yourself. The invoice after the job looks different. The number on the phone was still useful: you knew roughly what size of bill you were talking about, and you could compare two painters.

A tax calculator with six fields is that number on the phone. The tax return is the visit to the flat.

What six inputs are turned into

From the gross salary, the tax comparison takes off the statutory contributions to AHV, IV, EO and unemployment insurance. Then come the deductions the tax comparison applies without a receipt: the flat rate for work-related costs (Berufsauslagen), the insurance deduction at its statutory maximum (the calculator assumes your premiums reach that amount), the child deductions and, with two incomes, the dual-earner deduction. The federal and cantonal tariffs are applied to what's left, and the cantonal tax is multiplied by the tax multiplier (Steuerfuss) of the municipality you picked. If you tick the church box, you get church tax at the municipality's Reformed rate (the form has no denomination picker).

Behind it runs the same calculation TaxWize uses to prepare a real tax return: a fixed rule set per canton, not a language model. TaxWize uses AI where documents have to be read, and the tax comparison has no documents.

Your six inputs go to the TaxWize server in Switzerland for the calculation. TaxWize doesn't put your salary, marital status, children or church membership in a database, and doesn't write them to a log. As with any page request, the server's access log records the time and the IP address, and the canton you picked when the list of municipalities loads. Pick a canton outside the seven and the calculator shows you no number at all.

CHF 2'449.85 between Kilchberg and Maschwanden

A single person in the canton of Zurich, CHF 90'000 gross salary, no children, no church tax, tax year 2025. The tax comparison estimates for four municipalities:

The cheapest and the most expensive municipality are CHF 2'449.85 a year apart, on the same salary and in the same canton. The median of the 160 municipalities is CHF 10'253.15 for this person. Direct federal tax (CHF 1'375.25) and the cantonal tax are identical in all four rows, so the municipality's share is the part that moves. The Canton of Zurich puts it in one sentence: «Die Gemeinden setzen ihre Steuerfüsse selbst fest.» The municipalities set their multipliers themselves.

Next to the total, the result shows the split between Confederation, canton, municipality and church, the municipality's rank, and the names of the cheapest and the most expensive municipality. In the canton of Zurich the total also contains CHF 24 of personal tax (Personalsteuer), which has no row of its own in the split. Married couples get a field for the second income; leave it empty and the tax comparison calculates with one income.

Tariffs and multipliers change from year to year. These amounts belong to tax year 2025; for any other year, the figures valid for that year apply.

Where the estimate is off

Six fields leave a lot unasked. What's missing pushes the number in two directions:

The first row concerns employees with a pension fund. The contribution is printed on the salary certificate, and it differs from one pension fund to the next. There's no single rate that fits everyone and that I could have plugged in. So the calculator sets the contribution to zero, and that makes the estimated tax too high. That's deliberate: I'd rather have an estimate that the tax return corrects downwards than one that promises too much.

The wealth and income rows run the other way. If you have savings, a securities account or your own home, you pay taxes the calculator never asks about. For those households the estimate can be too low.

Why does the ranking still hold?

Within one canton, every municipality uses the same tariff. The municipality multiplies the basic cantonal tax (the amount the tariff produces) by its multiplier. A deduction shrinks the amount that multiplier works on. It doesn't touch the multiplier.

So if the person in the example has more deductions than the calculator assumes, their tax drops in all 160 municipalities. Kilchberg stays ahead of Zurich, and Zurich ahead of Winterthur. What gets smaller is the gap in francs, because the same multiplier now works on a smaller amount. How many francs a single deduction is worth is the subject of what a tax deduction actually saves.

For church members, the municipality's church tax rate comes on top, and it can shift the order. For everyone else: ask where you'd live more cheaply for tax purposes, and the estimate gives you a usable answer. Ask what you'll pay, and it gives you a first one.

From the estimate to the tax return

The Canton of Zurich describes its own calculator as an aid for the provisional calculation of the tax owed. That's true of every calculator, mine included. If all you want to know is whether a move changes your tax, you don't need to pay for that: the tax comparison is free, and the canton runs a calculator of its own.

The more precise number only comes from the documents. In TaxWize you upload the salary certificate, the Pillar 3a certificate, the health insurance statement and the rest of your paperwork. An AI on servers in Switzerland reads the values, and every value the AI reads can be checked and corrected. The calculation then runs on the fixed rule set that also sits behind the tax comparison. The pension fund contribution the calculator sets to zero now comes from your salary certificate.

That takes an account and costs CHF 39 per tax return and tax year. TaxWize prepares the 2025 return; you file it yourself through your canton's portal. Whether your deductions add up to something that brings the estimate down noticeably depends on your documents.

Sources

• TaxWize, tax comparison, tax year 2025: four queries for the canton of Zurich (single, gross salary CHF 90'000, no children, not a church member; municipalities Kilchberg, Zurich, Winterthur, Maschwanden) with total tax, rank, median and the split between Confederation, canton and municipality, plus the section "How does the tax comparison work?": https://taxwize.ch/en/tax-comparison (retrieved 12.10.2026)
• Canton of Zurich, «Steuerrechner» («Der Steuerrechner ist ein Hilfsmittel für die provisorische Berechnung des geschuldeten Steuerbetrags.», «Für die Steuerzahlung ist einzig der Betrag auf der Steuerrechnung massgebend.»): https://www.zh.ch/de/steuern-finanzen/steuern/steuern-natuerliche-personen/steuererklaerung-natuerliche-personen/steuerrechner.html (retrieved 12.10.2026)
• Canton of Zurich, «Aktuelle Gemeindesteuerfüsse» («Die Gemeinden setzen ihre Steuerfüsse selbst fest.»; the cantonal multiplier as a percentage of the basic cantonal tax): https://www.zh.ch/de/steuern-finanzen/steuern/steuerstatistiken/aktuelle-gemeinde-steuerfuesse.html (retrieved 12.10.2026)