Obesity remains prevalent in the UK leisure sector of horses and ponies. An inability among horse managers to recognize obesity in their animal will exacerbate this and preclude weight-loss initiation. The aim of the current study was to evaluate horse manager's perceptions of obesity and report on management factors that may influence the high obesity prevalence. A two-tier, Internet-based questionnaire was developed using lateral photographic images of horses/ponies (assigned a body condition score in vivo by an experienced assessor; tier 1). Respondent data gathered included the following: involvement in the equine sector, ability to identify overweight animals, and scoring suitability of animals for participation in different disciplines. Tier 2 (option to participate at conclusion of tier 1) gathered horse-owner information regarding animal management practices. Tier 1: Of 539 respondents, 98% (n = 528/539; 95% confidence interval [CI]: 96.3%–98.9%) were female. Amateur respondents (81%; n = 435/539; 95% CI: 77.1–83.8) exceeded professional respondents (19%; n = 104/539; 95% CI: 16.2%–22.8%). Only 11% respondents (n = 60/539; 95% CI: 8.7–14.1) correctly identified all overweight animals (6/12). A sport horse, cob horse, and pony were rated significantly lower (toward underweight) for competing in showing compared to other disciplines, tier 2: 177 responses. Owners reported obesity prevalence: 4.5% (n = 8/177; 95% CI: 2.3%–8.8%). Seasonal changes in horse/pony weight and management routines were reported. In conclusion, horse managers vary in their ability to visually identify overweight animals and consider it appropriate that animals intended for the show ring should carry more weight. Tier 2 adds to epidemiologic literature regarding UK equine management practices.