Objective This study tested whether core beliefs with themes of abandonment and rejection moderated the link between trait and behavioral excessive reassurance seeking (ERS) and interpersonal rejection. Method Participants were 118 women with high (n = 43; mean [M]age = 18.58, standard deviation [SD]age = 1.24) and low (n = 75; Mage = 18.58, SDage = 1.24) levels of depression symptoms and their male romantic partners. Couples reported their depression, ERS, abandonment/rejection cognitions, and relationship quality. We also coded women's reassurance‐seeking behavior during an audiotaped discussion task. Results Among women with high levels of depression symptoms and low levels of abandonment/rejection core beliefs, behavioral ERS was associated with lower partner‐reported relationship quality. Self‐reported ERS was significantly associated with partner relationship quality, but the effect was not moderated by depression or core beliefs. Conclusions ERS is a potent predictor of stress and subsequent depression. Our findings underscore the need to better understand factors (e.g., cognitions, partner characteristics) that may determine whether ERS behaviors beget interpersonal stress and rejection.