The paper investigates how financial technology might help countries promote renewable energy and reach the Sustainable Development Goals (SDGs). It is generally agreed that FinTech (financial technology) has the ability to help achieve the SDGs by 2030 and promote a sustainable society through technology-driven solutions. The financial sector has launched greener investment options in order to mobilize substantial financial resources towards climate neutrality in the coming decade. To achieve the Sustainable Development Goals and the goals set forth in the Paris Climate Agreement, however, this procedure must be accelerated. With the use of the innovative “quantile-on-quantile (QQ)” technique, this study uses the data of top FinTech economies for the period 1990–2020 and provides country-specific insights into the relationship between FinTech and renewable energy. Using quantile causality analysis, we may identify the direction of causality between these variables at the observed extremes. An extensive long-term relationship between FinTech and renewable energy was found in all countries. The leading FinTech economies show a positive association between the two at most quantiles, and a bidirectional causality relationship is seen across significant quantiles. This highlights the considerable yet variable impact FinTech policies have on renewable energy and vice versa in these innovative economies. These results highlight the connection between growing FinTech and promoting a green transition to further Sustainable Development Goals and provide useful insight for policy formulation.