The Internal Revenue Service said nearly 8,000 South Carolina residents have more than $10 million in unclaimed refunds from the 2010 tax year.

But they have to file returns for that period soon to claim the money. The grace period ends April 15.

"In cases where a return was not filed, the law provides most taxpayers with a three-year window of opportunity for claiming a refund," IRS spokesman Mark Green said in a statement today. "If no return is filed to claim the refund within three years, the money becomes property of the U.S. Treasury."

The IRS estimated the median unclaimed refund for 2010 in South Carolina is $532.

Nationally, about 918,600 taxpayers didn't file a federal income tax return for that year, leaving almost $760 million on the table.

"Taxpayers should review their 2010 statements for refundable credits and withholdings," Green said. "We want all taxpayers to get the refund they're due."

The IRS also said taxpayers seeking a 2010 refund that their checks can be held if they haven't filed returns for the subsequent years. In addition, refunds will be applied to debts owed to the IRS or state tax collectors. The refunds also can be used to offset unpaid child support or past-due federal debts such as student loans.