Perianal fistulae are a common complication of Crohn's disease (CD) and pose a substantial burden on quality of life. Data capturing health-related utility associated with perianal fistulae in CD are scarce. The current study aims to value health states related to different stages of the disease to quantitatively evaluate the impact of complex perianal fistulae on CD patients' quality of life. Eight health state descriptions associated with complex perianal fistulae in CD were developed following qualitative research with patients and validation by clinicians. Following pre-testing, a survey was administered online in two samples of UK respondents: the general population and patients with CD. A choice-based valuation technique, the time trade-off (TTO), was used for direct utility measurement. CD patients also valued their current health state using the TTO. Exclusion criteria for respondents displaying logical inconsistencies were applied. Usable responses were received from 835 respondents, reflective of the UK population in age and sex, in the general population survey and 162 CD patients in the patient survey. Non-remission states were valued much lower than the remission state by both samples, ranging from 0.20 for proctectomy with a negative outcome to 0.66 for chronic symptomatic fistulae with mild symptoms. Patients currently experiencing fistulae reported lower values for current health than those without fistulae. Low utility values were assigned to the non-remission health states for perianal fistulae in CD by the general public and patients with CD. This demonstrates the high humanistic burden of inadequately managed perianal fistula in CD.