The use of information systems in the rail sector has recently accelerated thanks to increasing innovations in digitalization and information technology in different transport sectors. Thus, investments in systems such as traffic information can bring substantial social value to the users, particularly during traffic disruptions. Investments in an efficient sustainable and scalable traffic information system could be an important complement to infrastructure investments and maintenance activities. In this context, we review existing research on traffic information systems, their different effects and more importantly, the assessment of their social value. We focus on the case of disruptions in railway passenger traffic although many discussions are about more general transport situations. The reviewed literature reveals several studies on the valuation of traffic information to passengers under different travel situations. However, we conclude that such valuations are rarely used in the context of cost-benefit analysis for planning investments for traffic information systems.