Recently, a general applicable numerical model for the simulation of steady electro-osmotic flow in rectangular micro-channels has been presented and evaluated based on available analytical Solutions [Anal. Chem. 74 (19) (2002) 4919]. This model combines the steady multi-ion transport model and the Navier-Stokes equations, and has been implemented in a finite element code. The model includes the ion distribution in the Helmholtz double layer and considers only one single electrical potential field variable throughout the domain. In this paper, the model is further evaluated through comparison with experimental data obtained in a so-called flow Field effect transistor or FlowFET [Science 286 (1999) 942]. It has been found that the numerical solutions are in very good agreement with the experimental data and with the commonly used slip boundary condition model. (C) 2003 Elsevier Science Ltd. All rights reserved.