Background: In patients undergoing open surgery for a ruptured abdominal aortic aneurysm (rAAA), survivors demonstrate a high platelet count, and proactive administration of platelets (and fresh frozen plasma) appears to influence mortality. Objectives: This trial investigated the effect of platelets administered before transport to surgery. Methods: In a prospective study design, patients were randomised to receive platelets (intervention; n = 61) or no platelets (control; n = 61) before transport to vascular surgery from 11 local hospitals. The study was terminated when one of the vascular surgical centres implemented endovascular repair for rAAA patients. Results: Thirty days after surgery, mortality was 36% for patients with intervention vs 31% for controls (P = 0·32). Post-operative thrombotic events (14 vs 15; P = 0·69), renal failure (11 vs 10; P = 0·15) and pulmonary insufficiency (34 vs 39; P = 0·15) were similar in the two groups of patients. No adverse reactions to platelet administration were observed. In addition, length of stay in the intensive care unit was unaffected by intervention. Conclusions: For patients planned for open repair of a rAAA, we observed no significant effect of early administration of platelets with regard to post-operative complications and stay in the ICU or in hospital and also no significant effect on mortality.