Antimicrobial drug use in companion animal medicine, the subsequent development of antimicrobial resistance and the potential hazard of animals transmitting resistant bacteria to humans are of increasing concern. Antimicrobial prescription patterns among companion animal veterinarians in the United States are understudied, and the association between antimicrobial drug use guideline awareness and antimicrobial drug prescription practices is unknown. Information on antimicrobial recommendations for five hypothetical clinical scenarios, including canine pyoderma, acute canine diarrhoea, feline lower urinary tract illness, canine dental procedures and feline upper respiratory illness, was gathered using an anonymous, online cross-sectional survey. A