The answer to this is the same answer to any good question, It Depends. Some grants are taxable and some are not. If you get a grant to start a business, I would assume you would have to treat that as taxable income but you would probably not pay any taxes on it because you would use the money to buy business deductible items like computers, office space, advertising etc. Grants and scholarships in excess of tuition, fees, books, supplies, and equipment are considered taxable income. Grants given to veterans not taxable. A lot of grants given out to pay your energy bills or help pay your mortgage are not taxable.