We apply a microeconomic time assignment model system to estimate and analyze the spatial differences in the values of work and leisure for relevant segments of travelers that work in Santiago, Chile, a large, spatially segregated South-American capital. The sample of 9,464 workers was obtained from the last OD survey; it includes weekly time use and individual socioeconomic characteristics, which represent quite accurately the differences across city zones. Seventeen segments are defined according to gender, age, family structure and zone of residence. Positive values of the marginal utility of work are obtained for women and youngsters, and negative for men and elders. Furthermore, women not having children showed larger values than mothers. These results are explained in terms of income hierarchy in the household and committed time.