Experimental isothermal vapor + liquid equilibrium (VLE) data are reported for the binary mixture containing 1-butyl-3-methylimidazolium bromide ([bmim]Br) + 1-butanol at three temperatures, 353.15, 363.15, and 373.15 K, in the range of 0-0.321 liquid mole fraction of [bmim]Br. Additionally, refractive index measurements have been performed at two temperatures, 298.15 and 308.15 K in the whole composition range. Densities, excess molar volumes, surface tensions, and surface tension deviations of the binary mixture were predicted by Lorenz-Lorentz (n(D)-rho) mixing rule. Dielectric permittivities and their deviations were evaluated by known equations. Vapor + liquid equilibrium data were correlated with the Wilson thermodynamic model while refractive index data were correlated by the 3-parameters Redlich-Kister equation. The studied mixture presents positive abatement from Raoult's law. Similarly, positive refractive index deviations are obtained. The VLE data may be used in separation processes design, and the thermophysical properties may be used as key parameters in specific applications.