Radiative heat transfer is an extremely important area of study as it is the only mode of heat transfer which can occur is the absence of a medium. When radiative heat transfer occurs at a distance d which is smaller than the characteristic wavelength of radiative heat transfer it has been extensively studied that the Stefan-Boltzmann law of radiative heat transfer cannot predict the heat flux between two bodies due quantum effects such as photon tunneling. Hence in the near field the radiative heat flux is several orders of magnitude greater than the corresponding black body radiation. This gives rise to extremely interesting applications of radiative heat transfer at the nanoscale and heat flux enhancement. Current analytical solutions to solve near field radiative heat transfer between two parallel plates overestimate the radiative heat flux between the two surfaces as the analytical solutions do not consider energy loss due to escaping electromagnetic waves. This is because the parallel surfaces are considered to be infinitely long when compared to the distance between the surfaces. But as science progresses and object sizes become smaller and smaller the assumption that surfaces are infinitely larger than the distance between them can no longer hold true. Therefore this thesis focuses on studying the near field radiative heat transfer between surfaces than can be considered finite sized and establish the difference between the analytical heat flux and simulated heat flux to establish these finite size effects and understand the energy loss due to finite sizes. In particular, this thesis studies the finite size effects due to change in length and width of the two parallel and change in gap size d between two surfaces. For analytical studies this thesis uses the semi-infinte parallel plane approach and uses a multiphysics software known as SCUFFEM which uses the fluctuating surface current approach alongside boundary element method to calculate temperature independent generalized flux which can in turn be used to calculate the energy transfer between two surfaces.