Background: Postpancreatectomy haemorrhage (PPH) and venous thromboembolism (VTE) are serious complications following pancreatic surgery. The aim was to assess the timing, occurrence and predictors of PPH and VTE. Methods: Elective pancreatic resections undertaken in a single university hospital between November 2013 and September 2017 were assessed. Three intervals were reviewed, each with a different routine regimen of nadroparin: 2850 units once daily (single dose) administered in hospital only, or 5700 units once daily (double dose) or 2850 units twice daily (split dose) administered in hospital and continued for 6 weeks after surgery. Clinically relevant PPH (CR-PPH) was classified according to International Study Group of Pancreatic Surgery criteria. VTE was defined according to a number of key diagnostic criteria within 6 weeks of surgery. Cox regression analyses were performed to test the hypotheses that the double-dose group would experience more PPH than the other two groups, the single-dose group would experience more VTE than the other two groups, and the split-dose group would experience the fewest adverse events (PPH or VTE). Results: In total, 240 patients were included, 80 per group. The double-dose group experienced significantly more CR-PPH (hazard ratio (HR) 2·14, 95 per cent c.i. 1·16 to 3·94; P = 0·015). More relaparotomies due to CR-PPH were performed in the double-dose group (16 versus 3·8 per cent; P = 0·002). The single-dose group did not experience more VTE (HR 1·41, 0·43 to 4·62; P = 0·570). The split dose was not associated with fewer adverse events (HR 0·77, 0·41 to 1·46; P = 0·422). Double-dose low molecular weight heparin (LMWH), high BMI and pancreatic fistula were independent predictors of CR-PPH. Conclusion: A double dose of LMWH prophylaxis continued for 6 weeks after pancreatic resection was associated with a twofold higher rate of CR-PPH, resulting in four times more relaparotomies. Patients receiving a single daily dose of LMWH in hospital only did not experience a higher rate of VTE.