Abstract: The present chapter aims at discussing macroscopic models used for space-discrete modelling of microwave susceptors. The main attention is focused at investigating the accuracy of the equivalent models in terms of power dissipated in the susceptor, which is of significant importance in microwave heating applications. The investigations supported with analytical calculations and numerical computations are conducted in a systematic manner leading to the determination of a practical limit for the application of macroscopic models. The discussion is summarised with the analysis of a real-life microwave heating simulation scenario to which previously formulated conclusions are applied.