The Internal Revenue Service says nearly 104,000 California taxpayers who did not file a 2011 federal income tax return may be missing out on $92.2 million in unclaimed refunds.

To collect the money, a 2011 tax return must be filed with the IRS by April 15.

In cases where a tax return was not filed, most taxpayers have three years to claim a refund. If no return is filed within three years, the refund money becomes property of the U.S. Treasury.

There is no penalty for filing a late return that qualifies for a refund.

In addition, the IRS said many low- to moderate-income workers may not have claimed an earned income tax credit, “which could potentially increase their refund,” said IRS spokesman David Tucker. For 2011, the credit is worth as much as $5,751.

Current and prior year tax forms and instructions are available on the IRS.gov or by calling (800) 829-3676.