One component of the stimulus plan was the distribution of $13 billion by the Social Security Administration, The Washington Post said. The money was to go to 52 million eligible beneficiaries in checks of $250 each.
Some of the dead individuals had not received benefits in 30 years, and would be as old as 136 if they were alive today.
The stimulus act only barred people who were incarcerated in the months leading up to the act's passage, meaning other inmates did receive checks. The SSA normally suspends payments when a beneficiary is incarcerated.
"Inaccurate payments are unacceptable. Social Security's Recovery Act payments were 99.8 percent accurate, and we quickly collected the majority of the inaccurate payments," SSA spokesman Mark Lassiter said.
Just over half the payments have been returned.