Abstract A two-dimensional numerical simulation study has been performed to model an electrohydrodynamic (EHD) micropump. The micropump consists of an array of interdigitated electrodes along the top and bottom of the micropump channel. The focus of the simulations was to study the effects of electrode gap, stage gap, channel height, and applied voltage. The numerical results were first validated with experimental data and then applied to obtain optimum electrode design and pump characteristics curves for geometries of interest. Additionally, the simulation results provide details about the flow behavior of the micropump and clearly capture local flow induced by EHD forces.