For families with three qualifying children or fewer, the child tax credit amount is refundable to the extent of 15 percent of taxable earned income in excess of $3,000 for 2010. For families with four or more qualifying children, the refundable amount may be the excess of the family's Social Security tax over the earned income credit, or the extent of 15 percent of taxable earned income in excess of $3,000, whichever is greater. Learn more about the child tax credit.
