Excess molar enthalpies, at the temperature of 298.15 K and atmospheric pressure, have been measured for the ternary system {x(1) 2-Methoxy-2-Methylpropane (MTBE) + x(2) 1-propanol + (1 - x(1) - x(2)) heptane}, over the whole composition range. Also, experimental data of excess molar enthalpy for the involved binary mixture {x 1-propanol + (1 - x) heptane} at the 298.15 K and atmospheric pressure, are reported. We are not aware of any previous experimental measurement of excess enthalpy in the literature for the ternary system presented in this study. Values of the excess molar enthalpies were measured using a Calvet microcalorimeter. The ternary contribution to the excess enthalpy was correlated with the equation due to Morris et al. (1975) [15], and the equation proposed by Myers-Scott (1963) [14] was used to fitted the experimental binary mixture measured in this work. Additionally, the experimental results are compared with the estimations obtained by applying the group contribution model of UNIFAC, in the versions of Larsen et al. (1987) [16] and Gmehling et al. (1993) [17]. Several empirical expressions for estimating ternary properties from binary results were also tested. (c) 2013 Elsevier Ltd. All rights reserved.