In France, the number of people practicing horse‐riding represents 3.6% of the population. The mortality rate varies between 0.6 and 1.7 per 1 million people and between 7.8 and 10 per 100,000 riders. The most common injury mechanism is falls from the horse, and the head is one of the most commonly injured parts. Currently, there is very little information available concerning the head impact condition for this kind of accident. The objective of the present work, therefore, is to identify the initial condition of head impact in the case of a horse rider experiencing a fall accident. A parametric study using multibody modelling to simulate a number of virtual accidents based on detailed real‐world situations allowed us to propose realistic rider’s head impact conditions in terms of normal and tangential velocity. Five parameters, such as the human posture, the initial horse velocity, horse kinematic, the orientation of the falls and the human size, have been varied. The results showed three main impact areas:​ frontal;​ parieto‐occipital;​ and temporo‐facial. The head impact velocities typically range from 6.6m/s to 7.5m/s, with an inclination versus normal to surface between 20deg and 30deg. These results will contribute to an improvement in standard tests for equestrian helmets, especially introducing motivated tangential impacts conditions.