Booking window is one of the critical characteristics of customer behaviour that can influence hotel sales performance. Previous studies were focused mainly on the importance of booking window reporting in revenue management with lack of evaluation. This paper focuses on the evaluation of revenue management activities by analysis of customer behaviour with a focus on the use of modern technologies (Booking Engine, Channel Manager). Results show that the selected hotel is not following basic revenue management principles, which can be a reason for the year-to-year decrease in direct online sales and overall poor performance.