Background In Latin America the experience in clinical practice with tofacitinib for moderate to severe Ulcerative Colitis (UC), in terms of both effectiveness and safety, is still limited. In Colombia, the incidence of UC as well as the availability of these new therapeutic options has been increasing, also, patients are frequently more refractory to treatments with higher rates of hospitalizations and surgeries. The aim of this study is to describe the real-life experience in Colombian patients with UC treated with Tofacitinib. Methods descriptive observational study, patients with moderate-severe UC as defined by the American College of Gastroenterology Ulcerative Colitis Activity Index (ACG score) treated with tofacitinib in induction phase (10mg every 12 hours) and maintenance (5mg every 12 hours), in different reference centers nationwide. Therapeutic response was evaluated in endoscopic (Mayo score), paraclinical (CRP, ESR, fecal calprotectin, hemoglobin) and clinical (absence of abdominal pain, diarrhea and rectorrhagia) terms. Additionally, the frequency of adverse events, steroid use and extraintestinal manifestations were measured. Results 51 patients, 55% women, the average age was 37,14 years (range14-72). All patients had moderate to severe UC; 73% patients with pancolitis, and 21,6% with left colitis. The mean age at UC diagnosis was 29,77 (SD17,8) years (range 12.77-66,4). And the mean time between disease onset and tofacitininb initiation was 7,33 (SD17,1) years (range 0.001-22.72). 42/51(82,4%) patients had previously failed tumor necrosis factor inhibitors and 15/51(29,4%) had failed alpha4 beta7 integrin inhibitor (Vedolizumab). Six patients were naïve to any biologic drug. Ten patients had extraintestinal manifestations. During the induction phase, 68,6% achieved clinical remission, 58,8% endoscopic remission, and 60,8% paraclinical remission. During maintenance phases, information was obtained from 18 patients during the first 6 months, 16 of whom reported clinical, paraclinical and endoscopic remission, while information was obtained from 7 patients at 12 months, 5 of whom showed clinical remission, and 6/7 endoscopic and paraclinical remission. Four patients reported adverse events No thromboembolic or cardiovascular events were reported. Conclusion Tofacitinib is an effective and safe therapeutic alternative in the management of moderate-severe UC in our population. It is safe in patients with previous use of anti-TNF and anti-integrin, without presenting thrombotic or cardiovascular events. Also, it is a promising alternative in the bio-naïve patient. Its use in pediatric patients is off-label, the patients included presented clinical and paraclinical remission.