For heavily loaded applications, film pressure within the hydrostatic thrust bearings is large enough to elastically deform the pad surface. Thus, the fluid film pressure envelope and associated performance parameters get altered. Therefore, to have an accurate prediction of bearing performance characteristics data, it becomes essential to address the elastic nature of the bearing pad while performing the numerical simulation. This paper investigates the combined influence of bearing pad flexibility and couple stress lubrication on the operation of an externally pressurized thrust bearing. Stokes couple stress theory is employed to obtain Reynolds equation to allow for the effect of the size of additives blended into the lubricant. A MATLAB based iterative source-code is developed to solve the modified Reynolds equation using FEM. It is found that the combined effect of couple stress lubricant and pad flexibility results in an overall increase of 63.79% and 10% in load-carrying capacity and film stiffness coefficient, respectively.