We aimed to evaluate rates of delivery and clinical manifestations of preterm severe preeclampsia in singleton and twin gestations.This retrospective cohort study included 86 765 deliveries from 2000 to 2009, including 3244 twins. Rates of delivery for severe preeclampsia among infants born 24 to 31+6, and 32 to 36+6 weeks gestation were calculated, and diagnostic criteria were compared.Re-term severe preeclampsia was more common in twin pregnancies (2.4% vs 0.4%, P<0.001, relative risk 5.70 (95% confidence interval 4.47 to 7.26)). This was also true for deliveries from 24 to 31+6 (0.8% vs 0.2%, P<0.001) and 32 to 36+6 weeks (1.7% vs 0.3%, P<0.001). Diagnostic criteria and disease manifestation including hemolysis elevated liver enzymes low platelet count syndrome, abruption and growth restriction were similar between groups.Twin pregnancies are significantly more likely than singletons to be delivered preterm for severe preeclampsia. Diagnostic criteria and disease manifestation were similar in singletons and twins, at all gestational ages.