Although some research suggests a link between procedural fairness and creativity, so far no study has directly tested whether a real manipulation of procedural fairness affects creativity. Additionally, research on procedural fairness effects consists mostly of unique studies, but more realistic, life-like longitudinal experiments with repeated fairness manipulations are lacking. This study investigated the influence of procedural fairness (i.e., having voice) on similar creativity tasks over a period of 4 weeks. Participants in the fair procedure condition maintained their level of creativity during the course of the experiment, whereas participants who were treated unfairly showed a decline in creativity. This research confirms the supporting role of conditions of procedural fairness regarding creativity and the importance of longitudinal designs to fully explore procedural fairness effects.