Small businesses and business owners may be audited for several reasons. Those can include a mismatch of your tax return and tax forms reported by other businesses, excessive expenses, business losses, missing income, and high deductions. If you underpay your taxes, you could also wind up getting extra attention from Uncle Sam. According to the IRS, there were 509,917 tax returns audited for the 2020 tax year, a very low fraction of all returns.