Introduction Bleeding after thyroid and/or parathyroid surgery is a life-threatening emergency. The aim of this study was to determine the rates of reoperation following bleeding, identify risk factors, assess management strategies and outcomes, and develop protocols to reduce risk and improve management of bleeding. Methods A retrospective cohort study of all consecutive patients who underwent thyroid and/or parathyroid surgery over a 7-year period was conducted. A nested case-control design was used to evaluate specific factors and their association with reoperation for bleeding. Results Of 1913 patients, 25 (1.3%) underwent reoperation for bleeding. Of the 25 patients who bled, 6 (24%) required reoperation before leaving theatre; 17 (68%) had bleeding within 6 h, 1 (4%) between 6 and 24 h, and 1 (4%) after 24 h. Reoperation for bleeding was not associated with age, gender, or surgeon. Patients who had total thyroidectomy were more likely to have reoperation for bleeding compared to hemithyroidectomy (p = 0.045) or parathyroidectomy (p = 0.001). The following factors were not associated with bleeding: neck dissection, redo surgery, drain use, blood-thinning medication or clotting disorders, and BMI. Patients who had reoperation for bleeding had longer hospital stay (p = 0.001), but similar rates of RLN palsy, wound infection, and hypoparathyroidism. Conclusion A higher risk profile for significant post-operative bleeding cannot be determined in patients undergoing thyroid surgery. Based on this experience, we developed protocols to reduce the risk of bleeding (the ITSRED Fred protocol) and for the early detection and management of bleed (the SCOOP protocol) following thyroid and/or parathyroid surgery.