Semiconductor–metal hybrid structures can exhibit a very large geometrical magnetoresistance effect, the so-called extraordinary magnetoresistance (EMR) effect. In this paper, we analyze this effect by means of a model based on the finite element method and compare our results with the experimental data. In particular, we investigate the important effect of the contact resistance ρc between the semiconductor and the metal on the EMR effect. Introducing a realistic ρc=3.5×10−7 Ω cm2 in our model we find that at room temperature this reduces the EMR by 30% if compared to an analysis where ρc is not considered.