Many older adults’ social experiences, physical activity (PA), and psychological well-being (PWB) were negatively impacted during COVID-19. We examined associations between social experiences and trajectories of PA and PWB during a period when public health restrictions were changing. 890 older adults (Mage = 65 years) responded to six monthly questionnaires. Latent growth curve models demonstrated good fit. Consistent with hypotheses, results indicated a significant (p ≤ .05) decline in stress, with higher descriptive norms associated with greater declines. Negative affect declined, but unexpectedly higher social participation was associated with slower declines. Positive affect and light PA had a quadratic trajectory where they declined, the rate of decline slowed, and they then increased again. Unexpectedly, higher social participation was associated with greater declines in positive affect. There were no predictors of change in light PA. MVPA declined from time 1-3 then increased, with a quadratic effect where the rate of increase slowed over time. The slowing rate of increase in MVPA was negatively predicted by social network size: those with larger social networks slowed their rate of increase of MVPA from time 4-6 more quickly. Findings indicate that while some social experiences were associated with adaptive outcomes, others may have presented vulnerabilities (e.g., greater social participation prior to periods of program closure may have been associated with less desirable changes in affect because they had more to lose). Further research on how the trajectories of social experiences and outcomes, PA, and PWB are associated may further elucidate these dynamic relationships.