Sedentary behavior has been found to be associated with negative health outcomes independently of physical activity in older adults. This systematic review collates interventions to reduce sedentary behavior in non-working older adults, assessing whether they are effective, feasible, and safe. A systematic search identified 2560 studies across five databases. Studies were included where participants were >=60 years on average with none younger than 45, and participants did not work >2 days per week. A total of six studies were identified, three of which included control groups, while the other three were repeated-measures pre-post designs. Only one study randomised participants. The overall level of quality of included studies was poor. A narrative synthesis was conducted, as the level of heterogeneity in outcomes and outcome reporting were too high for a meta-analysis to be performed. The narrative synthesis suggested that interventions have the potential to reduce sitting time in non-working older adults. Included studies reported feasible and safe implementations of their interventions in most samples, except for one subsample from a study of people in sheltered housing. Objectively measured reductions in sitting time were between 3.2% and 5.3% of waking time, or up to 53.9 min per day. Future studies should employ more rigorous designs to assess the effects of reducing sedentary behavior on health and physical function, and should include follow-ups to measure the duration of behavior change.