Interest on late payments and additional claims from the Old Age and Survivors’ Insurance (AHV) can be assessed retroactively for up to ten years. If the taxpayer does not voluntarily report the matter to the authorities or the police, the fine can be up to three times the amount of the additional tax. However, by voluntarily reporting the matter and demonstrating a willingness to cooperate, the fine can be reduced to up to one-fifth of the actual additional tax.

In addition to tax evasion, tax fraud is punished even more severely and can in some cases result in prison sentences. Tax fraud occurs when a person attempts to avoid paying taxes and deceive the tax authorities by forging or tampering with documents or records. As a result, funds—or tax revenue—are knowingly withheld from the government and, consequently, from the public and society. Therefore, fraudulently obtaining a favorable tax return is by no means a trivial offense.