In the present work the basic transport processes occurring in a planar solid oxide fuel cell (SOFC) were simulated. The Navier - Stokes and energy equations, including convective and diffusive terms, were numerically solved by the commercialCFD-ACE+ program along with the mass and charge transport equations. To achieve this, a three-dimensional geometry for the planar fuel cell has been built. It was also assumed that the feedstream was a mixture of methane and steam in a ratio avoiding carbon formation. In accordance with the literature, the steam reforming reaction, the water-gas shift reaction as well as electrochemical reactions were introduced to the model. The spatial variation of the mixture’s velocity, the temperature profiles and the species concentrations (mass fractions) were obtained. Furthermore, the effect of temperature on the produced current density was investigated and compared to the outcomes from isothermal imposed conditions.