Introduction: Seafaring is an extremely demanding profession that takes place in one of the most dangerous work environments possible. The unpredictable and demanding working conditions foster a high potential for risks and accidents. Objectives: To examine how sleep quality, fatigue and safety climate combine to influence perceptions of risk among seafarers. Method: Participants were 151 seafarers working in the deck or machine departments on board 11 ships belonging to a Norwegian company. Questionnaires were administered at two different time points, approximately one week apart. Results: Perceptions of risk of personal injuries and ship accidents increase when seafarers are fatigued. We also found that fatigue is related to poor sleep quality and that safety climate predicted both sleep quality and fatigue one week later. Conclusions The findings point to the importance for maritime organizations to be cognizant of the causes and consequences of fatigue among their employees, and that that policies and prioritizations are being perceived and interpreted by seafarers and may influence their sleep quality and vigilance when working at sea.