Integrating three theoretical explanations for declining rates of marriage in Japan, the authors develop hypotheses in which linkages between benefits of coresidence with parents and marriage timing are moderated by women's own socioeconomic characteristics. To evaluate these hypothesized interactive relationships, data from a panel survey of Japanese women is used to estimate hazard models for the transition from the parental home to first marriage. Results are consistent with the hypothesis that limited domestic responsibilities contribute to later marriage among coresident women with higher levels of human capital. Less evidence is found for the hypothesis that limited living expenses are associated with later marriage among women whose potential husbands are likely to have more tenuous economic prospects. The authors conclude that coresidence with parents plays a potentially important role in the marriage behavior of economically independent women in societies where family formation is relatively incompatible with full-time work for women. (Contains 3 tables and 3 notes.)