Today, investors are no longer solely concerned with a firm’s financial performance, they also consider its environmental, social, and governance (ESG) performance. Numerous scholars have analyzed either the drivers or the effects of ESG performance. In this study, we contribute to the first stream of literature by investigating the drivers of a firm’s eco-efficiency. Eco-efficiency denotes a firm’s capacity to optimize resource utilization for value creation while concurrently reducing its environmental footprint. It involves striking a balance between economic performance and environmental responsibility. By embracing eco-efficient practices, firms can enhance their long-term sustainability, reduce costs, and respond to the increasing consumer demand for environmentally responsible products and services. Our goal is to identify the governance factors, specifically board characteristics and activities, influencing eco-efficiency. We measure eco-efficiency using Data Envelopment Analysis (DEA) and focusing on efficiency measures aimed at minimizing inputs and ensuring Constant Returns to Scale (CRS model). We investigate the impact of board size, independence, gender diversity, and frequency of meetings on eco-efficiency, employing the beta regression model which aligns with our chosen dependent variable. Our analysis encompasses two distinct geographical contexts, Europe and the USA, to discern potential disparities between an environmentally regulated (Europe) and non-regulated (USA) contexts. We draw samples from the Europe Stoxx 600 index and the US S&P 500. Our findings reveal a positive correlation between eco-efficiency and board gender diversity across both US and European firms. We observe a detrimental effect of board size and meeting frequency on eco-efficiency among European companies. Furthermore, we identify a negative association between board independence and eco-efficiency for US firms. As far as we are concerned, this is the first attempt to identify the governance factors that affect eco-efficiency in the European and US context.