The minimum force needed for transporting glass microspheres across oil/water (O/W) interfaces was determined experimentally. From this data, the O/W contact angle was calculated with a mathematical model. First, the measured minimum centrifugal force was combined with a simplified model leading to an approximate contact angle. Then the results were refined by a numerical solution of the accurate mathematical model of particle transport through an oil/water interface. The contact angles calculated by the suggested approach were compared with the contact angles measured by goniometry on flat glass surfaces in the presence and absence of sodium dodecyl sulfate (SDS), Triton X-100, and Igepal CO-520 surfactants. The discrepancies were interpreted with the different surface chemistries/morphologies of glass microspheres and slides. The results show potential for this being a rapid screening method for chemical additives aimed at altering the wettability. This approach could be utilized in the oil and gas industry and especially to support enhanced oil recovery (EOR).