The relationship between ESG and firm value has been a relevant subject of study in recent years. We conducted a hybrid literature review to understand the literature's findings on this relationship and its implications in terms of cost of capital. First, a keyword co‐occurrence analysis on a 122 ABS ranked journals articles selection from Scopus database was adopted to identify and investigate the main research fields of the current literature. Then a content analysis through the bibliographic coupling of the most globally cited contributions was made, defining a final sample of 50 articles obtained through a minimum threshold of at least 15 total global citations (TGCs). We found that studies on the cost of debt configuration are more aimed at determining the implications on firm value, while most contributions on the cost of equity focus on the assessment of the risk–return profile for the investor or the construction of an ESG portfolio. Furthermore, we found that most of the literature has a consensus view on the lack of transparency behind the ESG ratings and their construction methodology, stating that disagreement on ESG ratings not only limits the results of empirical analysis, but can also negatively affect firm value due to a higher level of uncertainty.