Abstract: Background: There is limited real-world data on the long-term effectiveness and safety of tofacitinib among ulcerative colitis (UC) patients, especially among the elderly. Our aim was to evaluate these parameters among UC patients who had remained on the drug 1 year after initiation of therapy. Methods: We conducted a retrospective cohort study, utilizing the US National Veterans Affairs Healthcare System, including patients with UC who received tofacitinib. The primary endpoint was effectiveness at the end of follow-up. The secondary endpoint was to evaluate if the effectiveness was different among the elderly compared to the young. Adverse events associated with the drug, like herpes zoster, major adverse cardiovascular events, deep vein thrombosis, as well as infections and malignancy during follow-up were also assessed. Results: In total, 159 patients were included in the study, among whom 51 were in the elderly group and 108 were in the younger group. The median duration of follow-up was 1.47 years (range, 0.01-5.49 years). Effectiveness of tofacitinib among the cohort was 56.60% (90 out of 159 patients). The effectiveness was higher in the elderly (P = .005). Conclusion: In this nationwide cohort of UC patients, the effectiveness of tofacitinib was seen in a little over half the number of patients, with higher rates of effectiveness reported among the elderly. No new safety concerns were raised, especially among the elderly. Two-thirds of the patients on tofacitinib at the end of 1 year remained on the drug, with higher rates of effectiveness among the elderly and no new safety concerns. One patient with risk factors developed a major adverse cardiovascular event.