Sole proprietorships and partnerships (general and limited partnerships) are not obliged to be audited by external auditors. Other companies, on the other hand, are subject to ordinary audits if they exceed two of the following threshold values in two successive fiscal years (Art. 727 CO):
- Balance sheet total: CHF 20 million
- Turnover: CHF 40 million
- Full-time positions: 250
In addition, publicly owned companies and companies that are obliged to compile a group statement are always subject to ordinary audits. Companies that do not meet these criteria are subject to the limited audit or are completely exempt from the audit obligation. Various statutory special audits also exist, mostly audits of past-oriented financial information which need to be conducted according to statutory regulations.