Creating trust in online environments for users is the main goal of reputation systems. With the effort put into creating an efficient system there are some aspects that need to be further discussed. The aspects involved are the authenticity of the ratings, storage and the costly calculation methods. Blockchain offers potential in solving some of these issues and others due to its decentralized and immutable nature. The aim of this paper is to look into reputation systems and what benefits blockchain can offer and challenges that it could create.