The Earned Income Credit (EIC) is a refundable tax credit that has a significant impact on United States revenue. This course examines the earned income credit rules, the common errors made in claiming the credit, the consequences of its disallowance by the IRS and the requirements imposed on tax return preparers for earned income credit due diligence. The course discusses the rules applicable to everyone, the rules applicable only to individuals with a qualifying child and the rules that apply only when the taxpayer has a qualifying child. The requirements for tax return preparer due diligence are examined and best practices are identified.