An improved process for increasing the filling capacity of tobacco is provided in which tobacco is contacted with vapors of an expansion agent such as, for example, a low-boiling highly volatile hydrocarbon and/or halocarbon, at elevated temperature and pressure conditions, then releasing the pressure to about atmospheric pressure in a relatively short time period, such as from one second to ten minutes, so that the tobacco is expanded so as to increase its filling capacity in the absence of a subsequent heating step.