Ermessensveranlagung: when the Swiss tax office estimates your taxes

If you do not file your tax return despite a reminder, a bill still arrives. The tax office then assesses you at its dutiful discretion, an Ermessensveranlagung, called Ermessenseinschätzung in Canton Zurich. It estimates your income and wealth and serves you a decision. From the moment that decision is delivered you have 30 days to object, and the deadline cannot be extended. Objecting to an estimate is also stricter than objecting to an ordinary assessment: you can only challenge it for obvious incorrectness, you have to give reasons, and you have to name your evidence. Canton Zurich offers a shortcut most people do not know about. Submit the missing tax return after the decision, and that return is treated as the objection.

What a discretionary assessment is

The closest everyday parallel is a utility bill when you never sent in your meter reading. The building management bills you anyway, estimating your consumption, and not on the low side, because it has no interest in erring in your favour. The correction only comes when you supply the reading.

The tax office follows the same pattern. It may estimate if you fail to file despite a reminder, or if the tax factors cannot be reliably established from the documents available. The federal direct tax act expressly lets the office work from what it already knows about you. Cantonal and municipal taxes run on the same rule. In Canton Zurich the federal direct tax is assessed at the same time as the cantonal and municipal one.

How high does the tax office estimate?

Canton Zurich's own directive puts it in one sentence. The German original requires income to be estimated so that the taxpayer is presumably not better off for having failed to submit the return than if a complete one had been submitted.

That is the whole mechanism. The estimate is meant to be realistic, but it must not reward the non-filing. What Zurich pulls in: any earlier assessment, your employment and family circumstances, how your wealth has developed, your cost of living. On wealth it is more restrained, estimating only where you were already assessed with wealth or where new wealth can reasonably be presumed.

What an estimate systematically lacks is your deductions. The office does not know about your pillar 3a payment, your commute or your childcare costs.

What the missing deductions cost

An employee in Zurich was assessed for the 2024 tax period with taxable income of CHF 95'000. For the 2025 tax period he files nothing, not even after the reminder. The office estimates him at CHF 98'000.

His actual return would have carried pillar 3a of CHF 7'258, commuting and other professional expenses of roughly CHF 4'500, and childcare of CHF 3'000. Together around CHF 14'700 that never appears in the estimate.

At a marginal rate of roughly 20 percent across federal, cantonal and municipal tax, that is about CHF 2'900 of tax overpaid in one year. The reminder that led there currently costs CHF 35 in Aargau the first time round, a fraction of that.

About the figures: these amounts belong to the 2025 tax period and are worked here as an illustration. The ceiling and the rate that apply in your case are published by your cantonal tax office.

The 30 days start at your letterbox

The objection deadline is 30 days from delivery, counted from the following day. When you open the envelope is irrelevant. Zurich sends these decisions by A-Post Plus as a rule: trackable, but needing no signature, so the letter can sit in a pile while the clock runs. There, a decision counts as delivered once it has reached your sphere of control and you could have taken note of it. And if you culpably delay or prevent delivery, it counts as delivered at the moment it could have arrived without that delay.

The deadline cannot be extended. A late objection is only entertained if you can prove that military or civil service, illness, absence from the country or another serious reason prevented you, and that you filed within 30 days of that reason ending. Let the deadline pass and the estimate stands.

Why this objection is different

Against an ordinary assessment, setting out what is wrong is enough. Against an estimate, the law reverses the burden of proof.

Calling the estimate too high gets you nowhere, and neither does casting doubt on it. You have to show it does not match your actual circumstances, and name the documents that show it.

What belongs in the objection?

As a rule, exactly what was missing: the complete tax return with its supporting documents. That supplies the reasons and the evidence at once.

Canton Zurich has written this route into its rules. Submit the missing return after the assessment decision and it is treated as an objection. It goes to the municipal tax office, which forwards it to the cantonal tax office.

Two points get overlooked.

1. For federal direct tax, objection proceedings are free of charge as a rule. Costs of special investigative measures can still be charged where a culpable breach of duty made them necessary, and reminder fees already incurred do not disappear.
2. The authority can also correct against you. In objection proceedings it may reassess every tax factor and, after hearing you, change the assessment to your disadvantage. Rare when the return you file is complete, but a reason to fill it in carefully rather than optimistically.

The fine is a separate procedure

An estimate is an assessment, not a punishment. Alongside it there can be a fine for breaching procedural obligations, in its own procedure. It requires that a duty went unfulfilled despite a reminder, intentionally or negligently, and runs up to CHF 1'000, or CHF 10'000 in serious cases or on a repeat offence. Those are ceilings, not standard amounts.

Filing late but declaring everything keeps you inside that procedural law. Tax evasion is a different matter, with the fine measured against the tax evaded.

The way back is usually short

While no reminder is running, filing is the entire task. Once the decision is in the letterbox, two things matter most: the date on the envelope, and how complete the return you file afterwards is. What deadlines each canton grants beforehand is covered in the piece on extensions across the seven cantons. For a sense of where your municipality lands, the tax comparison works it through.

What eats the most time is gathering the documents and working out which deductions count. That is where TaxWize comes in: upload what you have, see what is still missing, and get the figures laid out so entering them in the cantonal portal is just transcription.

Sources

• Federal Act on Direct Federal Taxation (DBG, SR 642.11), as at 01.01.2026: Art. 130 para. 2 (assessment at dutiful discretion), Art. 132 paras. 1 and 3 (objection, obvious incorrectness), Art. 133 paras. 1 and 3 (start of the deadline, late objection), Art. 135 paras. 1 and 3 (decision, freedom from costs and the reservation via Art. 123 para. 2), Art. 174 (breach of procedural obligations), Art. 175 para. 2 (evasion): fedlex.admin.ch, retrieved 27.08.2026
• Tax Harmonisation Act (StHG, SR 642.14), as at 01.01.2025: Art. 46 para. 3, Art. 48 paras. 1, 2 and 4, Art. 55: fedlex.admin.ch, retrieved 27.08.2026
• Canton Zurich, Directive of the Finance Directorate on assessing taxpayers who have not filed a return despite a reminder (ZStB no. 139.2, issued 01.07.2025): zh.ch, retrieved 27.08.2026
• Canton Aargau, reminder fees for the tax return: ag.ch, Terminprobleme beim Einreichen, retrieved 27.08.2026
• Pillar 3a ceiling with a pension-fund affiliation, 2025 tax period: the ordinance states no franc amount but 8 percent of the upper BVG threshold of CHF 90'720, which is CHF 7'258. Ordinance on the tax deductibility of contributions to recognised pension schemes (BVV 3, SR 831.461.3), Art. 7 para. 1 lit. a, as at 01.01.2025, read together with BVG (SR 831.40) Art. 8 para. 1: fedlex.admin.ch, retrieved 27.08.2026