The volumetric properties of sulfur hexafluoride + pentane and sulfur hexafluoride + toluene mixtures have been determined at 323, 348, 373, 398, and 423 K at pressures up to 70 MPa using a variable-volume view cell. Densities for pure components and mixtures containing 90, 80, 70, 50, 40, and 30% by mass sulfur hexafluoride are reported as a function of pressure at each temperature.