Following our recent QSPR models for the glass transition temperatures of ammonium [1] and 1,3-dialkyl imidazolium-based ionic liquids [2,3], a similar model is reported in this work for remaining classes of ionic liquids. The roles of cations and anions are considered separately. The Genetic Function Approximation is applied to select suitable variables (molecular descriptors) and to develop a linear QSPR model. Consequently, a simple predictive model is obtained. Its performance is quantified by the following statistical parameters: absolute average deviation (AAD): 3.84%, determination coefficient: 0.8897, and root mean square error (RMSE): 10.594 K. (C) 2012 Elsevier B.V. All rights reserved.