The Internal Revenue Service paid out more than $13 billion in improper payments of a tax credit in 2013, according to a report released by the Treasury Inspector General for Tax Administration.
The earned income tax credit allows low-income workers to lower their tax bill and in many cases results in a significant refund check.
The report says the improper payments were between $13.3 billion and $15.6 billion. The IRS estimates that one quarter of all payments made for the credit in 2013 were issued improperly.
The IRS says it is aggressively fighting tax fraud, and is improving its efforts to police EITC payments. The agency says it has stopped nearly 15 million suspicious returns since 2011, blocking more than $50 billion in fraudulent refunds.