A semiempirical model for estimating the heat capacity of aqueous solutions of alkanolamines, both before and after CO2 absorption, has been developed, and the model parameters for several systems have been obtained using regression techniques. Furthermore, the heat capacity data for pure monoethanolamine (MEA), diethanolamine (DEA), N-methyldiethanolamine (MDEA), 2-amino-2-methyl-1-propanol (AMP), and piperazine (PZ), as well as the heat capacity data for aqueous solutions of the alkanolamines that have been reported in the open literature, have been analyzed. Given that the data reported by the several different authors for the same system were not weighted during the regression, key statistics of the model predictions against the experimental data set used in the model fitting have been used in the assessment of the relative accuracy of the experimental data reported by different authors for the same system. Overall, the model predictions are in excellent agreement with most of the experimental data that have been reported.