A processor may receive a transistor level integrated circuit (IC) design to be modelled. The processor may determine that the transistor level IC design has a first stage and a second stage. The processor may determine a first cross-current effective capacitance of the first stage and a second cross-current effective capacitance of the second stage. The processor may then determine a cross-current effective capacitance for the transistor level IC design by accumulating the first and second cross-current effective capacitances.