Support provision may enhance older adults’ well-being. Yet support for friends, a voluntary and socially engaging behavior, remains relatively understudied. This study examines daily support to close friends and its within-person links to mood, focusing on gender differences. Older adults ( n = 180, Mean age = 74.02, 57% female) completed 5–6 days of ecological momentary assessments, reporting on their positive and negative mood every 3 hours and support exchanges daily. Emotional support to friends being most common, followed by advice and practical help. Findings showed men were less likely than women to provide emotional support to friends. Older adults experienced greater positive mood on days they provided practical support. Men experienced lower positive mood on days they provided emotional support, a pattern not observed in women. Findings highlight gender differences in helping close friends, suggesting potential emotional costs for older men in providing emotional support.