Assessment by default: thirty days, and one single thing to prove.
Legal references verified on 21 September 2026.
When the return does not arrive, the authority assesses you itself, on the basis of an estimate. Contesting it is possible, but only one ground is admissible and the deadline does not extend.
What an assessment by default is
It is an assessment made by the authority on the basis of its own appreciation, where the taxpayer has not filed a return despite a reminder, or where the information provided does not allow income or profit to be determined.
The estimate is not designed to be accurate. It is designed not to disadvantage the tax authority, which almost always means a taxable base above reality.
The only admissible ground
Article 132 paragraph 3 of the federal direct tax act is explicit: a taxpayer assessed by default may file an objection only on the ground that the assessment is manifestly inaccurate. The objection must be reasoned and must indicate, where applicable, the evidence relied on.
Two practical consequences. First, saying the amount is too high is not enough: you have to produce the accounts, the return, the documents. Second, the burden of proof sits on you, whereas in an ordinary assessment it is shared.
The deadline
Thirty days from notification, as for any objection. It is a forfeiture deadline: once it has passed, the assessment becomes final, even if it is wrong.
- The starting point is the notification, not the date of the decision.
- An objection filed within the deadline but with no reasoning and no documents is inadmissible, not merely weak.
- It is better to file a reasoned objection and announce further documents than to let the thirty days run out.
What has to be produced
The rule is simple: to bring down an estimate, you have to replace it with an established figure.
- The complete return, filled in and signed.
- The annual accounts for the year concerned, with a detailed profit and loss account.
- The bank statements for the period.
- Receipts for the largest expenses.
- Where relevant, the VAT and payroll filings that cross-check the turnover.
That is exactly the work of an accounting catch-up, but with a thirty-day deadline instead of a calendar of your choosing. Which is why it is worth starting before the assessment by default arrives.
Can an assessment by default be void?
Voidness stays exceptional: it requires a particularly serious and manifest defect. In almost every case the route is an objection within thirty days, not voidness.
What if the deadline has already passed?
The assessment becomes final. Narrow routes remain, such as restoration of the deadline where a non-culpable impediment is shown, or revision in limited cases. None of them is a right: they are exceptions, and they have to be argued.
Does the fine disappear if the objection succeeds?
No. The fine punishes the failure to file, not the amount. A successful objection corrects the taxable base; it does not erase the procedural breach that caused it.
Do I need a lawyer?
Not for an ordinary objection. What decides the outcome is not the legal argument, it is the accounts. An accounting firm that produces defensible financial statements within the deadline is doing the useful work.
An assessment by default has just landed?
The clock is running. Send us the decision and tell us what documents you have: we will say straight away whether it is workable within thirty days.