To predict the critical micelle concentration of surfactants on the basis of any thermodynamic model, it is necessary to know the magnitude of the transfer free energy of the surfactant tail from the solvent to a hydrocarbon liquid phase. This information is not available for almost all of the polar organic solvents in which micellization behavior has been examined in the past. In this paper, we use the experimental infinite dilution activity coefficient data for alkanes obtained in other polar solvents to empirically correlate the transfer free energy to the solvent characteristics (as represented by the dispersion, polar, and hydrogen-bonding components of the solubility parameter). On the basis of this correlation, we suggest how one can determine the free energies of transfer of the surfactant tail from polar solvents of interest to a hydrocarbon liquid, at any temperature.