How does the tax code define “dependent” for tax purposes? The IRS has finalized the definition based on changes brought by the Tax Cuts and Jobs Act (TCJA) for tax years 2018 through 2025. The definition of dependent includes a qualifying relative who meets two tests. The “income test” is met if the individual receives gross income below the exemption amount in effect that year ($4,150 for this purpose only. For tax calculations, the exemption is zero). The “support test” is met when an individual receives more than half of his or her support from the taxpayer. The child tax credit of $500 may be available for certain dependents including qualifying relatives who aren’t children.