Heat capacities are fundamental properties of fluids for heat transfer applications. Accurate data can be generally obtained by experimental methods, which are usually expensive, difficult, and time-consuming. In terms of the calculations of heat capacities, many models have been proposed in the literature. Equations of state represent one of the most promising methods, but their performance has not been systematically studied and extensively reviewed. In this work, the calculations and performance of various equations of state for heat capacities are reviewed, and the different contributions to heat capacities are also discussed. The accuracy of the calculated heat capacities, as presented in literature, is also compared for some specific compounds, and the effects of different parametrization strategies as well as association schemes are analyzed. Finally, calculations for both associating and nonassociating compounds are performed using two association models, Cubic Plus Association and Perturbed-Chain Statistical Associating Fluid Theory equations of state, for a wide range of compounds for which the heat capacity results from literature are available.