[Excerpt] The Earned Income Tax Credit (EITC) is a refundable tax credit available to eligible workers with relatively low earnings. Because the credit is refundable, an EITC recipient need not owe taxes to receive the benefit. The credit is authorized by Section 32 of the Internal Revenue Code (IRC) and administered as part of the federal income tax system. In 2012, a total of $64.1 billion was claimed by 27.8 million tax filers, making the EITC the largest need-tested anti-poverty cash assistance program. Under current law, the EITC is calculated based on a recipient’s earned income, using one of eight different formulas, which vary depending on several factors, including the number of qualifying children a tax filer has (zero, one, two, or three or more) and his or her marital status (unmarried or married). All else being equal, the amount of the credit tends to increase with the number of eligible children the EITC claimant has. Indeed, most of the benefits of the EITC— 97% of EITC dollars in 2012—go to families with children. This report provides an overview of the EITC, first discussing eligibility requirements for the credit, followed by how the credit is computed and paid. The report then provides data on the growth of the EITC since it was first enacted in 1975. Finally the report concludes with data on the EITC claimed on 2012 tax returns, examining EITC claims by number of qualifying children, income level, tax filing status, and location of residence.