This study explores the link between the time older adults spend on lifelong learning and volunteering, examining how this association varies by socioeconomic status (SES) in South Korea. Employing fixed-effects regression models, we analyze six waves (2008–2018) of panel data from the Korean Longitudinal Study of Aging (KLoSA). Findings reveal an inverse U-shaped relationship between the time spent in lifelong learning and volunteering, with the high SES group showing a sharper increase and quicker decline in the association compared to the low SES group. This study emphasizes the importance of educational programs in encouraging volunteering among older adults. Additionally, the findings suggest a necessity for support systems to be established to assist older adults, especially those with lower SES, who may encounter difficulties in volunteering despite their willingness to engage in such activities.