This study examines disclosure on the sustainable development goals (SDGs) in firms’ annual reports. For a sample of European firms listed in the STOXX Europe-600 index and a reporting period of four years, we use textual analysis to assess both firms’ explicit reference to the SDGs in their annual reports as well as the implicit prevalence of SDG topics. In addition, we use content analysis to manually assess the quality of firms’ disclosure on the SDGs based on eleven reporting items. The results show a substantial increase in SDG reporting quality over time but a distinct lack of disclosure of quantitative and forward-looking information. Further analyses reveal the relevance of both financial and non-financial stakeholders. Specifically, SDG disclosure is particularly associated with a high relevance of socially responsible investors, customers or environment-related public pressure, while financial analysts, employees and the media are not associated with SDG disclosure.