Bin grand canonical Monte Carlo (Bin-GCMC) simulations are compared with conventional GCMC in a comprehensive investigation of the effects of simulation method for the description of the adsorption-desorption hysteresis of argon and benzene in graphitic slit pores. To study the equilibrium phase transition, we applied the Mid-Density scheme and show how pore width, length and adsorption temperature affect the equilibrium transition. It was found that the desorption branch becomes closer to the equilibrium transition as the pore length is increased, while its relative position between the adsorption and desorption segments of the hysteresis loop is rather insensitive to pore width and temperature. This is distinctly different from a previous study of cylindrical pores where the equilibrium transition was found to be closer to the adsorption branch of the hysteresis loop as the pore width is increased (Liu et al., 2012. Mol. Sim. 38 (3), 189-199). (C) 2012 Elsevier Ltd. All rights reserved.