The Kiddie Tax Ben Lee, 17 years old, meets the definition of a dependent for tax purposes. In 2023, Ben reported $500 of income from working at a summer camp and $12,750 interest from a trust fund established by Ben's grandparents. Ben's parents are subject to a 35 percent marginal tax rate. Ben's tax is computed as follows: Ben's total income Ben's standard deduction Ben's total taxable income Ben's unearned income Base amount Taxable income subject to kiddie tax Parents marginal rate Kiddie tax Tax on remaining income - Single rate 10% ($12,000 - $10,250 subject to kiddie tax) Total tax on Ben's Form 1040 $13,250 (1,250) $ 12,000 $ 12,750 (2,500) $ 10,250 35% $3,588 175 $3,763