Abstract The molar excess enthalpy H E has been measured as a function of mole fraction x at atmospheric pressure and 298.15 K for each of the six binary liquid mixtures: benzene + oxolane, and + 1,3-dioxolane, and tetrachloromethane + oxolane, + 1,3-dioxolane, + oxane, and + 1,3-dioxane. The overall consistency of the flow-calorimetric measurements is characterized by standard deviations from Redlich-Kister type smoothing equations which do not exceed ±1 per cent of the extreme value of H E. The mixtures with cyclic monoethers exhibit relatively large negative excess enthalpies, e.g. for (oxolane + tetrachloromethane) H E = −788.0 J mol −1 at x = 0.5. Mixtures containing cyclic diethers show rather small positive or negative excess enthalpies, e.g. for (1,3-dioxolane + tetrachloromethane), H E = 146.3 J mol −1 at x = 0.5, and for (1,3-dioxane + tetrachloromethane), H E = − 119.0 J mol −1. The latter mixture shows S-shaped dependence of H E on x with the very small positive section located at small mole fractions of cyclic ether.