The contribution of repulsive interactions between adsorbed molecules to the surface stress is explored using a uniform compression model. The model predicts relations between the surface stress, the surface coverage and the chemical potential of the gas phase which are tested with the help of experimental data on the surface stress for CO on Ni(100) in the high coverage regime. It is shown that the data are inconsistent with the assumption that the measured stress is due to repulsive interactions. The experimental data can be accounted for by assuming that the stress is caused by a modification of the electronic structure of the surface linear in the CO-coverage. Experimental data on the interface stress of Au(111) and Au(100) electrodes in 0.1 M HClO4 as a function of the electrode potential are analyzed. For Au(111) the stress is a linear function of the interface charge for potentials E-SCE between -0.2 and +0.5 V, consistent with earlier reports. For Au(100), however, the dependence of the interface stress on the charge is non-linear. For higher anodic potentials, corresponding to a higher density of adsorbed anions, the stress depends linear on the potential. It is argued that the stress at the solid-liquid interface is likewise due to an electronic effect and not caused by repulsive interactions.