Background: Canine leishmaniosis (CanL) due to Leishmania infantum remains common, and veterinarians do not always follow scientifically sound approaches for diagnosis, treatment and prevention. Objectives: To provide consensus guidelines for diagnosis and evidence‐based guidelines for treatment and prevention of CanL. Methods and Material: Clinical consensus guidelines for the diagnosis were structured based on literature and authors' experience. Three electronic databases were searched for randomised controlled trials, systematic reviews and meta‐analyses on treatment and prevention. Results, Conclusions and Clinical Importance: Diagnosis should be based on compatible clinical signs and/or clinicopathologic abnormalities, exclusion of differentials, demonstration of infection and increased concentration of anti‐ Leishmania IgG (quantitative serology). Euthanasia for public health purposes is not recommended and drugs with anti‐ Leishmania activity should be avoided in subclinically infected dogs. Recommended treatments include meglumine antimoniate‐allopurinol (first‐line treatment), miltefosine‐allopurinol (first‐line treatment) and aminosidine‐allopurinol (second‐line treatment); marbofloxacin may be considered in dogs with advanced chronic kidney disease. In endemic areas, recommended measures for prevention include deltamethrin 4% collar, flumethrin 4.5%‐imidacloprid 10% collar or permethrin 50%‐imidacloprid 10% spot‐on, not using infected blood products for transfusion, not breeding seropositive bitches or dogs with CanL, administration of domperidone (seronegative dogs) and dietary nucleotides‐active hexose correlated compound (subclinically infected, seropositive dogs). Vaccination with Li ESP with MDP may be considered, whereas protein Q vaccine is recommended in areas with very high rates of seroconversion. In non‐endemic areas, recommended measures include not using infected blood products for transfusion and removal of infected female dogs from reproduction.