A type of personal tax credit that reduces the amount a taxpayer must pay. The child tax credit is $1,000 (in 2008) for each child meeting the criteria the child must be a U.S. National, citizen, or resident under 17, a dependent of the taxpayer, and a grandchild, stepchild, child or foster child of the taxpayer. For taxpayers with income below $10,500, the child tax credit is refundable up to 10% of the income under $10,500. The tax credit is phased out for taxpayers with modified adjusted gross incomes over $75,000 (for single taxpayer), $110,000 (for couples), and $55,000 (for married couples filing separately).