Communicating about finances is essential to develop shared meaning and goals within couple relationships. When couples struggle to discuss finances, they can experience poor couple outcomes. For researchers and clinicians to effectively study and promote healthy couple communication patterns regarding finances, a parsimonious, reliable, and valid measure of couples’ financial communication is needed. This study examined the psychometric utility of the 5-item Couples’ Financial Communication Scale (originally developed for the Flourishing Families Project; Day, R. D., Bean, R., Coyne, S., Dyer, J., Harper, J., & Walker, L. (2017). Flourishing families project: Survey of family life [codebook].) using two large, diverse samples—one of emerging adult individuals in a romantic relationship (N = 1,950) and another of dyads in a romantic relationship (N = 1,252; 69.9% beyond emerging adulthood). Similar findings emerged across both samples. Inter-item correlations, skewness, and kurtosis of the five items were within acceptable ranges. The five items loaded onto a latent construct with robust standardized factor loadings (ranging from 0.63 to 0.90) and sound model fit. Cronbach’s alpha revealed sound reliability (α = between 0.85 and 0.89). Multiple tests of measurement equivalence suggest the measure appears to be reasonably useful across theoretically meaningful groups (gender, age, income, marital status, and joint banking behaviors). Couples’ financial communication and couples’ relationship quality were positively correlated with large effect sizes—showing initial evidence of predictive validity. The parsimonious Couples’ Financial Communication Scale has sound evidence of reliability, validity, and measurement equivalence across two diverse samples, which positions it to be a useful measure in future scholarship to assess the degree to which couples engage in ongoing healthy and cooperative financial communication.