442The Assurance of Corporate Sustainability Reports and the Renewed Role of Certified Auditors

The corporate sustainability reporting directive (2022/2464, CSRD) is expected to broaden its scope to include almost 50 000 companies in Europe. The directive sets two key obligations: (1) The annual management report must include information about certain sustainability subjects according to uniform standards; and (2) Sustainability reports must be controlled by an auditor or other authorized controller. This article focuses on examining the topic from an auditor’s perspective. Assuring the reliability of sustainability reports is essential to meet the objective of stakeholders getting reliable and comparable information. The aim of the article is to examine the renewed obligation to assure sustainability reporting, especially the key differences between the limited assurance level of sustainability reporting and the reasonable assurance level of statutory auditing. In addition, the article examines the narrowing of the expectation gap between the stakeholders and the actual content of assurance. If, in the future, sustainability information at the EU level is genuinely intended to be placed in the same category as the audit of financial information, then it is necessary to move from limited assurance engagements to reasonable assurance engagements. However, the issue must be carefully evaluated from the perspective of the administrative burden incurred by the companies, because it significantly increases the costs associated with the assurance of sustainability reporting for the companies. Finally, the goal is to evaluate how the assurance of sustainability reporting is regulated in Finland.443