Automotive seating rail structures are one of the key components in the automotive industry because they carry the entire weight of passenger and they are the holding structure for the seating foams and other assembled important components such as side airbag and seatbelt systems. The entire seating is supported firmly and attached to the bottom bodywork of the vehicle through the linkage assembly called the seat rails. These seat rails are adjustable in their longitudinal motion which plays an important role in giving the passengers enough leg room to make them feel comfortable. Therefore, seat rails under the various operating conditions, should be able to withstand the complete weight of the human with the seating structures, other assembled parts into the seating, and functional requirements such as crash safety which are important to avoid or minimize injuries to the occupants. Keeping the above requirements in view, the goal of this paper is to perform studies on the seat rails under different operating conditions through a detailed investigation using SolidWorks simulation tool for structural and vibration (dynamic) analyses with durability and design optimization using different grades of steel, aluminum, and multimaterials. Based on these studies a newly designed seat rail structure to increase the fatigue life, decrease the damage percentage, and increase the resonant frequencies are proposed.