Objective This study aimed to evaluate the preliminary effectiveness and feasibility of a theory-informed program to reduce sitting time in older adults. Design Pre-experimental (pre-post) study. Thirty non-working adult (≥60 years) participants attended a one hour face-to-face intervention session and were guided through: a review of their sitting time; normative feedback on sitting time; and setting goals to reduce total sitting time and bouts of prolonged sitting. Participants chose six goals and integrated one per week incrementally for six weeks. Participants received weekly phone calls. Outcome measures Sitting time and bouts of prolonged sitting (≥30 min) were measured objectively for seven days (activPAL3c inclinometer) pre- and post-intervention. During these periods, a 24-h time recall instrument was administered by computer-assisted telephone interview. Participants completed a post-intervention project evaluation questionnaire. Paired t tests with sequential Bonferroni corrections and Cohen's d effect sizes were calculated for all outcomes. Results Twenty-seven participants completed the assessments (71.7 ± 6.5 years). Post-intervention, objectively-measured total sitting time was significantly reduced by 51.5 min per day (p = 0.006; d = -0.58) and number of bouts of prolonged sitting by 0.8 per day (p = 0.002; d = -0.70). Objectively-measured standing increased by 39 min per day (p = 0.006; d = 0.58). Participants self-reported spending 96 min less per day sitting (p < 0.001; d = -0.77) and 32 min less per day watching television (p = 0.005; d = -0.59). Participants were highly satisfied with the program. Conclusion The 'Small Steps' program is a feasible and promising avenue for behavioral modification to reduce sitting time in older adults.