Gratitude and indebtedness are differently valenced emotional responses to benefits provided, which have implications for interpersonal processes. Drawing on a social functional model of emotions, we tested the roles of gratitude and indebtedness in romantic relationships with a daily-experience sampling of both members of cohabiting couples. As hypothesized, the receipt of thoughtful benefits predicted both gratitude and indebtedness. Men had more mixed emotional responses to benefit receipt than women. However, for both men and women, gratitude from interactions predicted increases in relationship connection and satisfaction the following day, for both recipient and benefactor. Although indebtedness may maintain external signals of relationship engagement, gratitude had uniquely predictive power in relationship promotion, perhaps acting as a booster shot for the relationship.