Several studies have shown that International Financial Reporting Standards (IFRS) adoption is associated with higher audit fees. We provide additional evidence on this issue by analyzing the Swiss context, which is particularly suitable for two reasons. First, it allows a better estimation of the impact of IFRS adoption on audit fees because the choice of accounting standards (IFRS, US generally accepted accounting principles [GAAPs] or Swiss GAAPs) is left to companies. Accordingly, comparisons can be made within the same institutional context. Second, it is also possible to measure the impact of IFRS renouncement on audit fees because Swiss companies following IFRS can switch back to Swiss GAAPs at any time. Based on a hand‐collected database including 1,651 firm‐year observations over 15 years, we show that, with the exception of very large companies, firms using IFRS pay higher audit fees. We also find that firms switching to IFRS incur additional audit fees in the year preceding the change. By contrast, the return to local GAAPs does not result in lower audit fees, which confirms the stickiness of audit fees reported by several prior studies.