Feeling younger than one’s chronological age–a younger subjective age bias–has been consistently linked to healthy aging. However, little is known about conditions under which such benefits are strengthened. In high-quality relationships, partners affirm individuals’ self-views and offer support that can encourage individuals to engage in behaviors compatible with their subjective age. Thus, we hypothesized the benefits of a younger subjective age bias would be stronger among adults in high-quality relationships. Hypotheses were supported in a 10-year longitudinal study of married adults (ages 34—84; N > 600): Relationship quality moderated the effect of subjective age bias on memory performance and heart rate variability, such that individuals in higher-quality relationships showed stronger beneficial effects of a younger subjective age bias. Results suggest psychological and relational resources may work together to jointly influence healthy aging. (PsycINFO Database Record (c) 2019 APA, all rights reserved)