Integrating the suffocation model of marriage with research on residential mobility, the current studies examined for the first time whether long-term romantic relationships are more central for residentially mobile (vs. stable) individuals (total N across three studies = 5,366; age range = 18-95). In Study 1, individuals who moved away from their place of birth (vs. not) were more likely to first confide in their spouse over other network members on important matters. In Study 2, history of frequent residential moves was associated with greater importance ascribed to romantic partners in the attachment hierarchy. In Study 3, the slope of perceived partner responsiveness predicting eudaimonic well-being got steeper as residential mobility increased. By showing the role of residential mobility in romantic relationships, our findings highlight the importance of studying socioecological factors to gain a deeper understanding of how relationship processes unfold.