Swiss Tax Bill: Provisional Bill, Instalments and Interest 2026
In Switzerland, your employer doesn’t deduct income tax from your salary unless you’re taxed at source. Instead, you get bills: first a provisional tax bill for the current year, then the final bill once your return has been assessed. The direct federal tax comes on a separate bill.
The provisional bill is a down payment, not an estimate you can ignore. Pay late and you pay interest. Pay early and some cantons give you more interest than a savings account. We’ll look at how both bills work, how to pay in instalments, when prepaying is worth it and what happens when someone can’t pay the bill.
In short:
- Provisional bill: a down payment for the current year, based on your last assessment. If your income changes a lot, ask for an adjusted bill.
- Final bill: arrives after the assessment. Payments, the withholding tax refund and interest are offset, and you usually pay the rest within 30 days.
- Prepaying: in 2026, prepayment interest is 0.75% in Zurich, 0.50% in Basel-Stadt and 0.25% in Bern, Aargau and St. Gallen. Lucerne and the federal tax pay none.
- Trouble paying: ask the tax office for instalments or a deferral before the deadline. Tax remission is the last resort for genuine hardship.
Provisional tax bill: what it is and when it arrives
The provisional tax bill, called provisorische Steuerrechnung, Akontorechnung or Ratenrechnung depending on the canton, is a down payment towards the current year’s cantonal and communal taxes. It’s based on your last assessment or on the tax you’re expected to owe. You only file the return for that year the following year.
Each canton decides when the bill goes out. In 2026 it arrived as early as January in some St. Gallen municipalities, in February in Aargau, by the end of May in Zurich and in June in Lucerne. Bern sends three instalment bills in May, August and November. Basel-Stadt doesn’t send a provisional bill for cantonal taxes at all: you estimate the amount yourself and pay it by the due date.
Provisional tax bill too high or too low?
The provisional bill doesn’t know your current situation. If you earn less, say after changing jobs, going part-time or having a child, you can ask the tax office for an adjusted bill. Aargau has a form for this, and in Lucerne you contact your municipality. For the federal tax, Zurich’s cantonal tax office has an online form to request an adjustment.
Simply paying less is not a good idea. Aargau sends a reminder with a fee if you pay only part of an unadjusted bill and can ultimately start debt collection. The city of Zurich, by contrast, lets you pay a recalculated amount with the blank payment slip, without a new bill.
If the bill is too low because you earn more, pay extra voluntarily. Otherwise the final bill brings a large balance, with interest in some cantons.
Final tax bill: the reckoning after the assessment
Once the tax office has reviewed your return, it sets your tax in the assessment notice (Veranlagungsverfügung). The final tax bill (definitive Steuerrechnung or Schlussrechnung) settles up: tax owed minus everything you’ve already paid, plus or minus interest. In Bern it arrives together with the assessment notice.
A balance is usually due within 30 days, for example in Zurich, Bern, St. Gallen and Lucerne. The deadline on your bill is what counts. If you’ve paid too much, you get the credit back or it’s offset against another tax debt. Basel-Stadt automatically carries surplus prepayments over to the next tax year, and Lucerne usually moves them to an open or the following year.
If the assessment is wrong, you file an objection (Einsprache). That’s a separate procedure from asking for instalments or remission.
Worked example: reading the final bill
Assumptions: canton of Zurich, cantonal and communal taxes for 2026 assessed at CHF 12,000. The provisional bill was CHF 10,000, paid on 30 September 2026. Your securities list shows CHF 350 of withholding tax.
| Item | Amount |
|---|---|
| Tax per assessment | CHF 12,000 |
| Already paid | minus CHF 10,000 |
| Withholding tax | minus CHF 350 |
| Balance before interest | CHF 1,650 |
Interest comes on top: on whatever is still outstanding after 30 September, Zurich charges 0.75% equalisation interest (Ausgleichszins) until the final bill. On CHF 2,000 that’s CHF 15 a year, and the outstanding amount shrinks once the withholding tax is credited. If you don’t pay the final bill within 30 days, the rate rises to 4.5% late interest.
Overview: due dates, instalments and interest in six cantons for 2026
Each canton runs its own collection. The table covers 2026 cantonal and communal taxes in six large German-speaking cantons, plus the direct federal tax. Rates are per year.
| Canton | Provisional bill | Paying | Due date for 2026 | Interest on prepayments | Interest on late payment |
|---|---|---|---|---|---|
| Zurich | By the end of May | Depending on the municipality, three instalments (30 June, 30 September, 31 December) or seven monthly instalments from June to December | 30 September 2026 | 0.75% | 0.75% equalisation interest until the final bill, 4.5% late interest if the final bill is unpaid after 30 days |
| Bern | Three instalment bills in May, August and November | 40%, 30% and 30% of the tax, each payable within 30 days. Monthly payments by standing order possible | 20 May, 20 August and 20 November 2026 | 0.25% | 4% from the 31st day after the due date |
| Basel-Stadt (cantonal taxes) | None, you estimate it yourself | Prepayments any time | 31 May 2027 | 0.50% | 3.5% from the due date |
| Aargau | February | Part payments of any size until the due date | 31 October 2026 | 0.25%, tax-free | 4.5% late interest from 1 November 2026 |
| St. Gallen | Depends on the municipality, January in Zuzwil | Three payments by 31 May, 31 July and 30 September. Some municipalities offer 9 or 11 instalments | 31 July 2026 | 0.25% | 0.25% equalisation interest until the final bill, 4% late interest if the final bill is unpaid after 30 days |
| Lucerne | June | In one go or continuously, including by standing order | 31 December 2026 | None | Equalisation interest 0% in 2026; arrears from 1 January 2027 use the 2027 rate. 4% late interest on overdue final bills |
| Direct federal tax | Early the following year | One bill | 1 March 2027, payable by 31 March 2027 | None | 4% late interest |
Two systems sit behind the last column. Zurich, St. Gallen and Lucerne use equalisation interest: whatever is missing on the reference date costs a low rate until the final bill, in Lucerne even 0% in calendar year 2026. Only an overdue final bill costs full late interest. Bern and Aargau charge the high rate on amounts that are actually owed, were billed and are still unpaid after the deadline, Basel-Stadt on everything unpaid after the due date. The Basel row covers cantonal taxes; Riehen collects its communal taxes at its own interest rates. Zurich instalments in October and December are paid after the due date and therefore cost 0.75% equalisation interest.
Direct federal tax: its own bill and deadlines
The cantons collect the federal tax, but it follows its own rules. It only falls due on 1 March of the following year and must be paid within 30 days, so by 31 March 2027 for 2026. A bill you pay in March 2026 therefore usually covers tax year 2025.
Prepaying doesn’t pay off here: interest on voluntary prepayments is 0% in 2026 and 2027, and late interest is 4%. The rates are listed in the ESTV overview.
Paying Swiss taxes in instalments
For the provisional bill, most cantons don’t require permission to pay in instalments. In Zurich it’s three instalments or seven monthly ones, depending on the municipality, Bern splits the tax into three instalment bills and lets you divide each one further yourself. In Lucerne and Aargau you pay as many part payments as you like until the due date, including by standing order. What matters is that everything is paid by the due date, otherwise interest runs.
My tip: set aside a twelfth of the expected tax every month, or pay it straight to the tax office by standing order. Then neither the provisional nor the final bill will surprise you.
The final bill is different. To pay it in instalments, you need a payment arrangement. The city of Zurich lets you apply online for up to six instalments the first time you ask. Instalments aren’t automatically interest-free: Bern charges late interest even during an agreed arrangement, and Zurich grants federal tax instalments only with late interest too.
Paying taxes early: is the prepayment interest worth it?
If you pay before the due date, many cantons credit you prepayment interest (Vergütungszins). In 2026 that’s 0.75% in Zurich, 0.50% in Basel-Stadt and 0.25% in Bern, Aargau and St. Gallen. Lucerne and the federal government pay nothing.
For comparison: the Zürcher Kantonalbank savings account pays 0.05% up to CHF 25,000. Cembra’s Sparkonto Plus pays 0.60%, but you can only withdraw CHF 20,000 every 180 days, with six months’ notice above that. A few small banks pay up to 1%, for example Caisse d’Épargne d’Aubonne with twelve months’ notice for withdrawals above CHF 10,000 a year. My savings account comparison shows which accounts currently lead.
Worked example: Zurich
Assumptions: you pay CHF 10,000 towards your 2026 cantonal and communal taxes at the end of January, eight months before the 30 September due date.
| Where the money sits for eight months | Rate | Interest |
|---|---|---|
| Prepayment to the canton of Zurich | 0.75% | CHF 50 |
| Cembra Sparkonto Plus | 0.60% | CHF 40 |
| Zürcher Kantonalbank savings account | 0.05% | about CHF 3 |
In Zurich and Bern, both the prepayment interest and savings interest are taxable income, so you can compare the rates directly. In Aargau, interest on prepayments is tax-free.
Prepayment interest of 0.25% is above ZKB’s savings account at 0.05%, but below Cembra’s Sparkonto Plus at 0.60%. Prepaying only makes sense for money you definitely won’t need before the due date. Your emergency fund never belongs with the tax office. Treat prepayments as tied-up money: whether you can get a credit back before the final bill depends on the canton. Basel-Stadt pays out credits of CHF 100 or more on request at any time. Bern also only accepts prepayments up to roughly the expected annual tax, and only if no taxes from earlier years are outstanding.
Late interest: what paying late costs
Late interest is far higher than any savings rate. In 2026 it’s 4.5% in Zurich and Aargau, 4% in Bern, St. Gallen, Lucerne and for the federal tax, and 3.5% in Basel-Stadt. An example: paying CHF 3,000 from a Zurich final bill three months late costs CHF 33.75.
When it starts depends on the canton. In Bern from the 31st day after the due date, in Aargau from the day after the due date. In Zurich, St. Gallen and Lucerne, only the low equalisation interest runs until the final bill; late interest starts if you don’t pay the final bill within 30 days. The exact rules for Bern are on the Bern tax office’s interest page.
If someone doesn’t pay at all, a reminder with a new deadline follows, then debt collection (Betreibung). Whether that costs extra depends on the canton. Zurich charges no reminder fees, Aargau charges CHF 35 for the reminder and CHF 100 for starting debt collection.
Can’t pay your Swiss tax bill: deferral, instalments, remission
If someone can’t pay the tax bill by the deadline, the most important step is to contact the tax office named on the bill before the deadline passes. Ideally in writing, with a reason and a realistic proposal of how much is possible each month. There are three routes, from the easiest to the narrowest.
Instalments. The tax is paid in fixed parts. This is the usual route for a temporary squeeze, for example after a large final balance. For the provisional bill it’s often possible without a request; for the final bill you need an arrangement.
Deferral (Stundung). The deadline is moved and the tax paid later in one go. For the federal tax, the law allows deferral and instalments if paying on time would cause substantial hardship. The tax office can ask for security and revoke the arrangement if the payments aren’t kept.
Tax remission (Steuererlass). All or part of the tax is waived. This is the last resort and narrowly limited:
- Only in genuine hardship. For the federal tax, paying must mean great hardship, for example because the person’s means don’t cover the subsistence minimum under debt collection law, or because the debts can’t be repaid in the foreseeable future despite cutting back.
- Instalments come first. If deferral or instalments can solve the situation, remission is refused in whole or in part.
- For the person, not for other creditors. Paying other creditors first or living beyond one’s means can lead to refusal.
- With documents. The application needs the household’s income, expenses, assets and debts, with evidence. Bern has its own form that includes a current monthly budget.
- At the right time. For the federal tax, you can only apply once the assessment is legally final, and you must apply before the payment order (Zahlungsbefehl) is served. A remission application doesn’t stop collection; interest and deadlines keep running.
For cantonal and communal taxes, cantonal law applies, but the principles are similar. If tax debts come on top of other debts, a debt counselling service such as Caritas helps draw up a plan for all creditors.
What lowers your tax bill: withholding tax and pillar 3a
You get the 35% withholding tax on Swiss interest and dividends back through your tax return. The canton offsets it against cantonal and communal taxes or pays it out. Bern usually credits it in the final bill. Basel-Stadt books it as a prepayment at the start of the year in which the tax falls due, provided you claim the refund in that same year. How to declare it correctly is explained in my guide to reclaiming withholding tax.
Your biggest lever comes before year-end: pillar 3a contributions are deductible from taxable income. The ordinary maximum for 2026 is CHF 7,258 with a pension fund and 20% of net earned income, at most CHF 36,288, without one. The money must be in your 3a account by 31 December. If you didn’t pay in the full amount in 2025, you can, under certain conditions, also make up the gap, up to CHF 7,258 in 2026. How much tax that saves is covered in my guide to the third pillar.
Conclusion: paying your tax bill without unnecessary interest
The provisional bill is a down payment, the final bill the reckoning. Pay on time and you pay no late interest, and in some cantons money paid early earns more than a savings account. The key points:
- Prepaying: compare your canton’s prepayment interest in the table above with your savings rate, and only pay in money you definitely won’t need before the due date.
- Your income has changed a lot: ask for an adjusted provisional bill rather than just paying less.
- A bill can’t be paid on time: ask the tax office for instalments before the deadline. Remission is only for genuine hardship.