Recently, intercity bus companies has adopted an innovative 'Presidential Seating' configuration (19-21 seats per standard bus) to provide long haul service in Taiwan. The purpose of this study is to discuss the suitability of this kind of service in view of bus service quality and resource allocation. An analytical model is developed to find the optimal number of seats that minimizes the total social cost. The model considers not only operators' cost and users' cost but also freeway congestion cost due to a more frequent schedule. Based on the assumptions that the number of buses is unlimited, the demand of passengers will not vary with different types of seating, and passengers arrive uniformly within each period, the optimum number of seats is directly proportional to the square root of the passenger demand, the bus turnaround time and the bus operating cost, and is inversely proportional to the waiting time value, the ratio of waiting time to headway, and the load factor. A demand survey of the Taipei-Taichung Line was conducted in order to proceed an empirical study. The results show that the intercity bus service is seriously short of capacity because of the variation of demand and turnaround time. The ratio of waiting time to headway is larger than 2. According to the existing passenger demand of Taipei-Taichung Line, 33 or 45 seats per bus is more suitable and efficient for intercity bus service, while not the so-called 'Presidential Seating' with only 19 seats per bus.