In many companies, it can be noticed that the share of project work is increasing. At the same time, many of these projects miss their deadlines and exceed their budgets. A major challenge when facing multiple critical projects at the same time is the correct prioritization of these projects. If one project is prioritized, it usually means that others will be delayed. This often ignores the fact that delaying the other projects will lead to additional cost, missed revenue or delayed savings for these projects. By taking these factors known as cost of delay into account better decisions can be made. Therefore, the aim of this paper is to develop a methodology, which shows how organizations can integrate the cost of delay into their project management for assisting in project prioritization decisions.