The COVID-19 pandemic has corroborated environmental degradation and climate change as two important problems of the twenty-first century. To turn environmental challenges into opportunities, we need environmentally friendly, green financial technologies. This article aims to shed light on the studies within this field, by building a bridge between financial technology (FinTech) and cryptocurrencies. A cashless society is expected to be fostered as digital currencies become more widespread, which will result in the eventual replacement of notes and coins. When considered from this point of view, cryptocurrencies could be regarded as environmentally friendly. On the other hand, the large amount of energy consumed in the mining process of cryptocurrencies questions their environmental friendliness. Therefore, analyzing whether cryptocurrencies are environmentally friendly or not conducted in a holistic approach.