It depends on what you paid the CPA for. If you paid him or her to prepare a tax return for your business, or to do other accounting work for your business, you can deduct it as a business expense under "Legal and professional services." But if you paid the CPA only to prepare your personal tax return, you cannot deduct it. Under the new tax reform law, the cost of tax return preparation is not deductible on your federal tax return for 2018 through 2025. Some states might allow the deduction.