Patients with haemophilia are now widely advised to participate in sports. However, no extensive data are available about their actual participation. A self-administered questionnaire was used to investigate sports participation by persons with haemophilia in the Netherlands. All 293 questionnaires that were distributed have been returned; 217 were from people with severe haemophilia A or B (this is 40% of the severely affected Dutch population with haemophilia). Of this group, 155 (71%) participate in one or more sports: 66 swim, 36 cycle, 21 play tennis, 18 do fitness exercises, 16 ice skate, 10 ski and 10 play table tennis; in total 44 different sports are mentioned. Of a group of 16 persons with haemophilia who are unable to run, 10 (63%) participate in sport and of a group of 91 who can only run sometimes, 64 (70%) engage in sports. This shows that there are ample opportunities for persons with haemophilia to participate in sports, even if they are unable to run. Severely affected persons with haemophilia are as active as the general Dutch population; in fact, a higher proportion swims and/or cycles. In conclusion, sports participation in the Netherlands by persons with haemophilia is in accordance with World Federation of Hemophilia directives.