Hypo-and anorexia are the most commonly presented complaints for many diseases in veterinary medicine, leading to malnutrition, immunosuppression, compromised wound healing and altered drug metabolism. Stimulating appetite and palatability are therefore important factors in managing anorectic pets. The palatability of a liquid nutritional supplement for cats (LNScat) and dogs (LNSdog), which can be added to the diet as appetite stimulant, was evaluated in healthy pets. In total, 60 cats and 60 dogs of different ages and breeds were included in the study. Acceptance tests were performed using LNS with a concentration of 100% (LNS100) and preferences of water and three different concentrations of LNS (LNS50, LNS70, LNS100) were tested using a traditional twopan preference test. Acceptance tests with LNS100 showed that cats and dogs generally accepted LNS very well. In dogs, a weak positive correlation existed between acceptance and age, whereas in cats no correlation with age was observed. Furthermore, preference tests showed a clear preference for LNS, regardless of dilution (LNS50, LNS70 and LNS100), when compared to water. In cats, LNS100 was generally better accepted than LNS50 and LNS70. Dogs preferred LNS70 and LNS100 to LNS50. The present study demonstrated that LNS is highly palatable for healthy dogs and cats. If future research confirms that LNS is also highly palatable for ill and hospitalised patients and stimulates appetite in a hospital setting, a practical tool to improve moisture and nutrient intake in patients with hypo-or anorexia will become available.