A detailed analysis of non-financial and sustainability reporting may indicate companies’ attention to and responsibility regarding environmental, social, and economic aspects. This article investigates the correlation between environmental performance as a non-financial metric and financial performance. Simultaneously, it identifies the categories of environmental information provided by companies and the implicit responsibility with which they address environmental protection issues. Data were collected from the sustainability reports of 668 companies in Romania for the 2019–2021 period. The study uses, on the one hand, a diagnostic analysis method (the grid method) to determine the environmental performance (environmental score) of the companies. On the other hand, it uses a linear regression model to test the correlation between environmental performance and financial performance (including a tolerance analysis to identify multicollinearity, forward variable selection, backward variable selection, and the Durbin-Watson test). The study’s findings underscore a positive correlation between environmental non-financial performance and financial performance. In particular, high turnover and advanced age of the company are associated with high non-financial performance.

We begin with a simple but uncomfortable question for many firms: if an environmentally unfriendly company decided to become environmentally performant, what would actually happen to its turnover? Would sustainability represent merely ’the price of doing good’, or would it be closer to an investment with a financial return? Should shareholders view it as a financial risk or as a financial opportunity? To answer these questions, our research combines a measurable Environmental Performance (EP) index, firm-level data from all large Romanian companies reporting sustainability measures, and a combination of deep learning and optimization techniques. We provide evidence that becoming environmentally performant is less about incurring costs for ethical principles and more about creating opportunities for improved financial performance. Environmentally unfriendly firms that would transition toward sustainability would experience a median turnover increase of 3.52%. Moreover, 56.64% of firms would experience a positive effect, with a median gain of 15.61% within this group. For the remaining 43.36%, the median decline of 9.38% is more appropriately interpreted as a short-term adjustment cost rather than a structural penalty, consistent with the existing literature.