The agency estimates that 1 million taxpayers could potentially have a claim to some money with a median unclaimed refund amount of nearly $850 but if you didn't file your taxes from 2014 time is running out to claim your share.

The IRS says students and part-time workers are among those due for a refund who are likely to have overlooked filing a return.

For those owed a refund, there is no penalty for filing a late return.

By law 2014 returns must be postmarked by April 17, 2018.