BOISE, Idaho — Thousands of Idahoans have left more than $5.2 million on the table in unclaimed tax refunds - and the deadline to claim that money is coming up fast. 

The Internal Revenue Service said Thursday that more than 5,200 people in Idaho did not file their Form 1040 federal income tax return for 2015, meaning they missed out on getting their money back from the government. By federal law, the refunds must be claimed by April 15, 2019 or that money will get handed over to the U.S. Treasury. 

Nationwide, the money is even higher, the IRS said. 

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"We're trying to connect over a million people with their share of $1.4 billion in potentially unclaimed refunds for 2015," IRS Commissioner Charles Rettig said in a release. "Students, part-time workers and many others may have overlooked filing for 2015. And there's no penalty for filing a late return if you're due a refund."

The IRS estimates the midpoint for the potential 2015 is $879.

Those who haven't filed their 2015 taxes can request their wage forms for that year -like  the W-2, 1098, 1099 or 5498 - from their employer, or order a free wage and income transcript at using the Get Transcript Online tool.