Intrahousehold finances offer a window into the crossroads between the market domain’s emphasis on self-reliance and the family domain’s emphasis on interdependence. Modern couples confront tensions between ideals of mutual family interests and values of individualism, a departure from fitting themselves into culturally expected family arrangements of the past. How these social changes impact progress towards gender equality is not well understood. The dissertation aims are to: (1) identify mechanisms associated with different types of money arrangements in families, and (2) examine the association between financial arrangements and gender inequality in families. To meet these aims, I used data from two sources. First, I used multinomial modeling of 2012 International Social Survey Programme data to show cohabiting couples in countries with greater gender equality partially integrated their money instead of keeping it separate. Married couples pooled money regardless of country-level gender equality. Findings suggest that different cultural logics operate in married and cohabiting partnerships across gendered contexts, rather than cohabitation functioning as a weaker form of marriage. Second, I devised a novel survey experiment to collect the first nationally representative sample of U.S. adults’ attitudes about income sharing in families. Results challenge the notion that marriage distinctively encourages support for financial integration in families. Findings also revealed that respondents believed higher-earning partners ought to hold back a greater absolute value of their earnings for personal use, allowing inequality in labor market rewards to perpetuate unequal conditions within families. I also used this data to disentangle the mechanisms associated with perceptions of decision-making authority. Findings indicated higher relative-earners within families were not regarded as entitled to the final word in decisions. Whether respondents considered earnings individually or community owned did not explain the lack of association between relative earnings and decision-making clout. Instead, findings showed a significant association between the fictional decider’s gender and respondents’ perceptions of fairness. Specifically, when women were presented as the decider over monetary family choices, unilateral decision making about monetary items was viewed more favorably. Collectively, these findings suggest gender socialization theories are essential to explaining persistent gender inequality in families.