Isentropic compressibilities, kappa(s), and excess isentropic compressibilities, kappa(s)(E), of various halohydrocarbons, namely, chlorocyclohexane, chlorobenzene, bromocyclohexane and bromobenzene in isomeric butanols were calculated from density and speed of sound measurements at 298.15 K. Excess isentropic compressibilities were fitted to the Redlich-Kister equation. Mixtures containing an aromatic halohydrocarbons show a decrease in the kappa(s)(E) values with respect to those containing the corresponding halocycloalkane. The same effect can be observed when the chlorine atom is substituted by bromine.