The research objective is to analyze how companies address their contribution to the United Nations Sustainable Development Goals (SDGs) to manage their legitimacy. Reaching the SDGs by 2030 is considered vital for the well-being of humanity and the planet with multiple parties challenged to contribute. This requires changes in current routines, including the “business as usual” of companies, as achieving the SDGs without companies is unlikely. However, how companies address their contribution to the SDGs is unexplored. Informed by legitimacy theory, FTSE 100 reports on sustainability performance are analyzed deductively with a classification scheme, complemented by an inductive thematic analysis. Two-thirds of companies address the SDGs and legitimize their contributions by mapping the SDGs to existing activities or using them as inspiration for future activities, either for their core business or sustainability as an add-on. The resulting four legitimization strategies - conciliatory, transparency, stimulation, and transformation - largely indicate symbolic rather than substantive disclosure without changes to the “business as usual”. The paper contributes to literature and practice by developing a framework of four corporate legitimization strategies and evaluates these efforts critically. The paper concludes that at this point, while all four strategies might be suitable from a legitimacy perspective, if the aim is to achieve the SDGs by 2030, the dominantly symbolic legitimization strategies are insufficient.