High-risk hospitalized younger adults (age ≤60) have 30-day readmission rates comparable to Medicare fee-for-service patients. This younger cohort has a high incidence of comorbid mental health and substance use disorders, which increases the complexity of their postdischarge care. Although few care transition studies have enrolled younger adult patients, findings from our previous work suggest that these patients have postdischarge needs requiring different approaches than those serving elderly patients. Our current pilot study, situated in a safety-net system, targets this younger population, employing a social worker as the Transition Coach (TC). Social workers are explicitly trained to address psychosocial complexities, and we evaluated whether our TC intervention could improve hospital-to-home transitions by assisting patients with medication management, attending follow-up appointments, and addressing medical, psychiatric, and psychosocial needs. Primary outcomes were Patient Activation Measure scores on admission and 30-days postdischarge; outpatient follow-up at 7 and 30 days; and all-cause, in-network 30-, 60-, and 90-day readmissions. At 30 and 60 days, no differences were observed in the primary outcomes; at 90 days, intervention patients demonstrated a trend toward readmission reduction. A social worker-led transitional care program shows promise in reducing readmissions over 90 days among high-risk, lower socioeconomic, nonelderly adult patients.