Introduction: Transfusion strategy for trauma patients with massive haemorrhage is often incorporated in massive transfusion protocols (MTP). Albeit correct MTP use results in better patient outcome, research regarding the state of MTP knowledge is scarce. The objective of this study is therefore to assess knowledge of local MTP and massive transfusion strategy in the level 1 trauma centres in the Netherlands. Our hypothesis is that actual MTP knowledge is low and transfusion strategy differs. Materials and methods: Surveys were sent out in January 2020 to all trauma and vascular surgeons, anaesthesiologists, emergency department physicians of the largest level 1 trauma centre (locally, n = 113) and to one trauma surgeon, emergency physician and anaesthesiologist in each of the nine other governmentally assigned level 1 trauma centres in the Netherlands (nationally, n = 27). The respondents were subdivided into a frequent user group (MTP usage ≥ 4 times in 2019) and a non-frequent user group (MTP usage < 4 in 2019). Data are expressed as numbers and percentages. Results: Response rate was (n = 48; 42%) for the local survey and (n = 14; 52%) for the national survey. Locally, (n = 23; 48%) and (n = 25; 52%) respondents were defined frequent and non-frequent users respectively and national respondents all as frequent users. In total, (n = 13; 27%) of local respondents were aware of the current local composition of the MTP. Respondents indicated to transfuse erythrocytes first, followed by plasma and platelets (local non-frequent users n = 23; 92%, local frequent users n = 21; 91% and national frequent users n = 13; 93%). The indication for platelet transfusion was units erythrocytes transfused (local non-frequent users n = 10; 40% frequent users locally n = 11; 48% and nationally n = 5; 36%) and clinical view (local non-frequent users n = 9; 36%, frequent users locally n = 8; 35% and n<5 nationally. Whereas few respondents claimed (n = 5; 21% non-frequent users locally and n <5 nationally) to transfuse ...