Using the only national time use survey in Chilean cities (2015) we analyze the weekly assignment of time of individuals, aimed at revealing the hierarchy and substitutions that underlay the observed time assignment, controlling for the effect of socioeconomic variables. This is achieved by means of a model that captures the effects of both types of variables simultaneously, isolating the pure substitution effects between activities and detecting their hierarchy. We find that the differences across genders—universally observed—regarding time assigned to paid and unpaid labor, and to sleep, happens due to a reduction in time assigned to leisure by women. We also find that an inhabitant of the capital city—about six times larger than the second in population—substitutes sleep and leisure time for time assigned to transportation, to all types of work, and to eating. Leisure exhibits strong substitution with transportation, and also with time assigned to work (paid and unpaid), to study, and to eating.