In Canada, any costs incurred to care for and maintain a service dog are allowable as a deduction IF the animal is provided by a person or organization whose main purpose is to train such animals. Things such as costs for certification, annual local licencing fees, food, grooming, veterinary bills, (especially for routine checks, vaccinations) etc. In BC, these dogs must be certified to qualify. Does this mean owner-trained dogs do not qualify? This is a grey area and one to ask your income tax person about.