(Vapour + liquid) equilibrium data for (ethanol + methanol + 2-methoxy-2-methylbutane) were measured and compared with predictions from group-contribution methods. The experimental data were determined in a still that recycled both liquid and vapour phases, and their thermodynamic consistency was demonstrated using Wisniak＇s L-W test, and Wisniak and Tamir＇s modification of the McDermott-Ellis test. The data were correlated using the Wilson, NRTL, and UNIQUAC equations in order to calculate the activity coefficients. Of the ASOG-KT, UNIFAC, UNIFAC-Lyngby, and UNIFAC-Dortmund group-contribution methods, the latter resulted in the smallest deviations between the experimental equilibrium temperature and vapour-phase composition and the calculated values.