This paper explores the dynamics of waiting lines in department stores, utilizing queuing theory to analyze and optimize customer flow. Knowing customer actions, transaction processes, and peak hours to manage them effectively is given significance as it improves service efficiency, cuts customer wait time in the queue, and helps the business to spread their service fast at the peak moments. This observational study was conducted at a department store to obtain customer arrival rates and service times data. These include the arrival and service rates, the distribution of service time, and the queue discipline. These results underscore issues facing waiting line management, from long queues to customer dissatisfaction to the requisite number of hours of service needed to manage demand. To address this problem, the study proposes various solutions to enhance queue management, including cashier service rate adjustment, the design of additional queue lines, and technology to give customers live updates about their waiting time. The paper concludes by discussing the significant role of queue management in customer satisfaction, service efficiency, and profitability of departmental stores. Keywords: