Recently, structural optimisation has developed vastly with the advent of high speed computers and advances in Computer Aided Engineering (CAE). With today's tool and technology advancement, it is possible to perform all types of optimisation according to the requirement. Structural optimisation is usually performed as a Linear Static response optimisation because of its simplicity, even though in real world most automobile load cases are non-linear in nature. Equivalent Static Load (ESL) structural optimisation is a structural optimisation method where equivalent static loads are utilised as external loads for linear static response optimisation. The ESL is defined as the static load that generates almost the similar displacement by a non linear static/dynamic analysis. This type of approach can significantly save time and manpower during the initial stages of the vehicle development program. This paper discusses about the development of a Weight Optimised Body In White (BIW) structure from an already existing baseline model satisfying both the crash and NVH minimum structural performance requirements. All the basic loads are converted into equivalent static loads with appropriate assumptions. Once, ESLs are obtained correlation was carried out with available CAE results/targets of the baseline vehicle. Sufficient care was taken to consider enough number of loads, those will determine the structural integrity of the weight reduced (optimised) model.