Domestic horses can exhibit a range of unwanted and abnormal behaviors, ranging from biting to stereotypies. The demographic of horse owners is changing towards new and increasingly urbanised leisure owners who may lack the experience to cope with behavioral problems and may have restricted access to land and facilities; both representing potential welfare concerns. A large-scale Internet survey was used to quantify the type and prevalence of handling and stable-related behavior problems within the UK leisure horse population, and to identify associated management routine risk factors. Data were collected for 1230 horses with 82% of these expressing one or more, primarily low frequency, behavior problems. Principal components analysis extracted five distinct components, indicating that the behavior problems were not displayed randomly. These were: handling issues (57% of horses), frustration behavior (52%), abnormal oral/ ingestive behavior (48%), aggressive behavior (33%), and locomotor stereotypies (22%). Logistic regression analyses were used to explore associations between each of these behavior components and management routine. Time spent stabled was associated with an increased risk of handling, oral/ingestive and aggressive problems. Features of the turn-out group were risk factors for all behavior problem components except aggressive behavior, with an established turn-out group containing 7-9 other horses associated with the least problems. Frustration behavior had the largest number of associated risk factors and these primarily represented an increased risk when full social contact was thwarted in the field and stable. Handling and stable-related behavior problems are highly prevalent within UK leisure horses, albeit at low frequencies. Time at grass and the opportunity to form proper social relationships are key risk factors, with traditional stabling practices at odds with these. The increasing urbanisation of leisure horses must be addressed by management practices, such as group housing, that permit full social relationships when turn-out is limited.