If you work alongside your dog, you may be able to claim a tax deduction for certain expenses. Ranchers and farmers who use dogs for herding or guarding livestock can usually write off the cost of buying, training, and feeding their dogs. In 2002, one farmer took his claim for cat and dog food to the Tax Court of Canada. The court ruled the deduction was allowable because the animals were guarding his blueberries. This ruling hinges on the fact that the farmer was growing blueberries for business purposes. However, you can’t claim any deductions for a pet dog, regardless of which plants he guards. Additionally, if you have a service animal, you may be able to claim a deduction for expenses related to that animal. These expenses are medical expenses, not business expenses. For example, imagine you own a salon and you have a service dog for your epilepsy. You bring your dog to work every day, but that doesn’t mean the expenses are deductible from a business standpoint. Instead, you can report the costs as medical expenses, just as you would with medications you take during work. If you incur dog-related expenses as part of running a business, you can usually claim those costs as business expenses. That includes ranchers and farmers but could also include dog groomers, pet sitters, and similar professionals. In most cases, though, dog-related expenses are not deductible, even if your dog is your favorite sidekick on the job.