This study focuses on the development of reliable methods for predicting heats of combustion of ionic liquids. A review of 18 existing empirical correlations giving heats of combustion developed in the early times of combustion science has been performed and re-examined in a scientifically sound manner for their ability to predict heats of combustion of ionic liquids. On the basis of a database of appropriate thermodynamic data established for 53 ionic liquids, the work showed that at least five models making use of constitutional descriptors give pretty good predictions. Moreover, a new purpose-built model for heats of combustion of ionic liquids has been developed using a multilinear regression. The model obtained from a training set of 40 molecules, meeting Organization for Economic Co-operation and Development guiding principles, revealed a good fit with literature values (R-2 = 0.989). This work is considered a starting point for better consideration of the safe use of ionic liquids in the context of green chemistry and biorefining.