Belief in animal sentience and the quality of human-animal relationships play a significant role in animal welfare. However, the link between an individual animal's welfare and the beliefs and emotional connection of the owner to the animal is understudied and focussed on single cultures, limiting generalisability. In this study, we explored potential links between owner attitude, beliefs in animal sentience, and working equid welfare across four continents. This study used a welfare assessment protocol alongside a questionnaire exploring owner attitudes to assess 378 participants across six countries. Overall, the general health status and body condition of equids belonging to owners with an affective (versus instrumental) perspective and those owners who believed that their equids could feel emotions, were significantly better. Equids belonging to owners who believed that their animals could feel pain were also significantly less likely to be lame. Potential causal relationships between factors and theories explaining these beliefs are discussed. These results can inform future welfare initiatives by highlighting the importance of the human-equid relationship and the role that beliefs regarding animal sentience play in influencing equid welfare.