Vapour pressures of n-butanol with 2,2-dimethylbutane and with 2,3-dimethylbutane between 283.15 and 313.15 K were measured at 5 K intervals by a static method. At 298.15 K, experimental excess enthalpies and excess volumes of n-butanol with 2,3-dimethylbutane were also measured. Vapour pressures of both alkanes have been fitted to Antoine equations. At 298.15 K and x = 0.5, H(E) values calculated from the Gibbs-Helmholtz equation compare favourably with the experimental ones. The ERAS model gives a qualitative description of V(E) and reproduces quantitatively the experimental results of G(E) and H(E), at 298.15 K.