Background Adherence to smoking, alcohol consumption, diet and physical activity (PA) guidelines may improve outcomes for people with a stoma. A better understanding of these behaviours following stoma formation surgery and their experiences and attitudes towards receiving lifestyle advice, could help identify specific gaps and inform interventions going forward. The aim of this study was to describe changes in current lifestyle following stoma formation and to explore concerns, desire for lifestyle information, advice and support among people who have or have had a stoma. Methods A sample of adults who currently had or in the past had a stoma for treatment for any medical condition was recruited online through relevant charities and companies, and invited to complete a cross-sectional, online survey. Consenting participants (n = 425) provided demographic information and completed brief, validated questionnaires about their lifestyle, alongside questions around their concerns regarding permanent stoma and experiences of lifestyle information and advice. Responses were summarised using descriptive statistics, and associations between reported concerns about stoma and changes in health behaviours were explored. Results Most respondents (93%) still had a stoma at the time of completing the survey. The majority (80%) had not consumed at least 5 portions of fruit and vegetables on the previous day and 20% reported they had not participated in at least 30 min of physical activity on any day in the previous week. Most respondents were non-smokers (84%) and did not exceed recommendations for alcohol intake (60%). Most (56%) felt their PA had decreased following stoma formation. Frequencies of concerns about a permanent stoma were high, and appeared to be associated with reported decreases in PA. Of those reporting nausea, 40% felt their diet had worsened since having their stoma. A large proportion of respondents had not received PA (42%) or dietary (30%) advice, and of these > 90% would have liked guidance.