Abstract Objectives The high psychological burden of inflammatory bowel diseases (IBD) underscores the need for effective and feasible psychological treatment options. This study aimed to explore the acceptability and feasibility of mindfulness-based cognitive therapy (MBCT) for adults with IBD. Method This mixed-methods study was embedded in a multicenter randomized controlled trial on the effectiveness of MBCT in IBD. Reasons for participation were discussed in the context of the trial and reasons for non-participation were collected from one of the participating centers. Semi-structured in-depth interviews about facilitators and barriers were conducted with a purposive sample of 22 participants from the MBCT groups. For triangulation purposes, participant observation and a focus group with involved mindfulness teachers were incorporated. Themes were interpreted using reflexive thematic analysis. Results The primary reason for participation was to improve coping with stress and mental health problems, often alongside reducing physical symptoms and disease activity. Active invitation of the healthcare provider encouraged enrolment. Lack of need for psychological care and time constraints were prominent reasons for non-participation. Facilitators included peer support, the possibility to attend online, and personal commitment. Barriers included time investment and the impact of disease activity and fatigue. Conclusions This study can serve as a base for refining MBCT to optimize accessibility for IBD patients. Recommendations included the active involvement of healthcare providers in suggesting MBCT to patients and the use of digital (self-help) alternatives for those who prefer self-scheduled practice over peer support and therapist-led engagement. Preregistration The trial was registered on November 30, 2020, at ClinicalTrials.gov under the identifier NCT04646785.