One way older adults may be able to maintain emotional well-being despite declining in cognitive ability is through leveraging social resources for intrinsic interpersonal emotion regulation. Additionally, given their increased life experience, older adults might also be particularly well-suited to regulate the emotions of others. To examine age difference in use and effectiveness of intrinsic interpersonal emotion regulation, community adults (N = 290, aged 25-85 years) were prompted 6×/day for 10 days to report their emotional experience, use of intrinsic emotion regulation strategies (including capitalization, social sharing, co-reappraisal, and reminiscing), and interaction partner age. Older age was associated with being less likely to engage in social sharing of negative emotions, and this effect was stable when controlling for negative emotion experience. Otherwise, there were no age differences in how often or how effectively people use intrinsic interpersonal emotion regulation. In terms of interaction partner age, older partner age was only associated with greater likelihood of using co-reappraisal and higher reports of negative emotion after social sharing. In summary, there was no strong evidence for the idea that interpersonal emotion regulation becomes more (or less) common or effective with age. However, though people may be less likely to share negative emotions and be seen as less effective partners for sharing these emotions later in life, older adults are preferable social partners for co-reappraisal potentially due to their life experience. Future work should explore motivational (i.e., attitudes toward negative emotions) and cultural (i.e., perceptions of roles and emotional abilities) mechanisms. (PsycInfo Database Record (c) 2024 APA, all rights reserved).