Do you operate a small business? You can deduct the costs involved in bringing in new customers and keeping existing ones, including advertising and marketing expenses. The expenses must be ordinary (common in your industry) and necessary (appropriate for your business). The IRS reminds business owners that among the expenses you generally can’t deduct are amounts spent to influence legislation, or gifts or contributions to political parties or candidates. This includes advertising in the convention program of a political party or any other publication if the proceeds are for the use of a political party or candidate. Here’s more about business expense deductions: