Obsessive–compulsive tendencies may render individuals vulnerable to elevated distress and over-adherence to safety behaviours during illness outbreaks. The present study investigated obsessive beliefs as a predictor of obsessive–compulsive symptoms, COVID-19 distress and the exercise of safety behaviours related to COVID-19 in a community sample. Four hundred seventy-nine participants responded to a questionnaire battery in March 2020 and 218 individuals participated in a follow-up assessment in September 2020. Results indicated that baseline obsessive beliefs predicted the exercise of baseline safety behaviours through obsessive–compulsive symptoms and COVID-19 distress. In addition, the relationship between baseline obsessive beliefs and safety behaviour adoption 6 months later was mediated by later obsessive–compulsive symptoms and COVID-19 distress. Findings extended prior research on the association between obsessive–compulsive phenomena and psychological changes related to illness outbreaks. The implications for prevention and treatment strategies are discussed.