The kiddie tax is a set of tax laws which force unearned income over a small amount to be taxed at the higher tax rate of the parents. For 2015, the kiddie tax limits allows $1,050 to be received without being taxed and the next $1,050 to be taxed at the child’s rate, while any unearned income in excess of $2,100 is taxed at the parent’s top marginal rate.