In this work, we report the molar enthalpies of formation of ethyl 2-, 3-, and 4-hydroxybenzoates in gas-phase at T = 298.15 K, derived from experimental techniques such as static-bomb combustion calorimetry, differential scanning calorimetry, and thermogravimetric analysis. We calculated as well the enthalpies of formation (of the same compound set) in gas-phase through the Gaussian G4 composite method, and a Boltzmann averaging procedure weighted with the Gibbs free energy. Finally, we discuss and compare experimental and theoretical results. (C) 2017 Elsevier Ltd.