Despite previous attempts to link hotel rating systems to performance, no prior study has examined the effects of changes in Diamond ratings. Considering the variability in Diamond ratings, and the fact that hotels may gain or lose a Diamond over time, it is important for hotel properties to assess such outcomes on key performance indicators (KPIs). Hence, this study examines the influence of Diamond rating changes on hotels’ KPIs and competitive set indexes, which allow to benchmark a property’s performance against a designated competitive set.