Prevention of ABO-incompatible red cell transfusions (ABO-it) requires accurate donor and patient identification and correct application of processes for transfusion safety. In France and Germany, a bedside identity check and ABO compatibility test are performed. In the UK, an identity check, often structured as a bedside checklist, is performed with or without electronic patient identification (ePID). To compare the efficacy of ABO-it bedside preventive measures, frequencies and causes of ABO-it between 2013 and 2022 were investigated in all three countries. Despite differing bedside safety measures, similar average ABO-it frequencies were observed in France (0.19 [SD:0.09]/100 000 issued red cell units) and in the UK (0.28 [SD:0.17]/100 000), whereas a higher frequency (0.71 [SD:0.23]/100 000) was observed in Germany which has similar bedside safety measures to France. ABO-it resulted mostly from erroneous patient identification and transfusion of a red cell unit intended for another patient. In France and Germany, all ABO-it were associated with incorrectly performed identity check and ABO compatibility test. In the UK, most ABO-it were associated with incorrectly performed identity checks. Current measures to prevent ABO-it are not fully effective. Further development and implementation of effective patient identification systems, including electronic information systems, across the entire transfusion process, should be considered.