All taxpayers who earn less than $157,500, or $315,000 for a married couple, can now deduct 20 percent of the income they receive via a pass-through businesses from their overall taxable income. If taxpayers earn above those amounts and aren’t service professionals, they must meet tests to take the full deduction -- the size of their deduction depends on how much they pay in employee wages or how much they’ve invested in capital like real estate.