Talk about sweet justice. If you’ve ever thought you’re paying too much in taxes — ya think? — here’s your chance to maybe claw some of it back from the government.

Every year, the IRS bemoans how much money taxpayers needlessly wind up forfeiting to Uncle Sam — $1 billion is the latest approximate annual figure — because of costly mistakes made when filing or even failing to file returns. And every year, taxpayers make the same (or new) mistakes all over again.

Well, now through April 30, H&R Block (www.hrblock.com) is offering free “Second Look” reviews of 2008 to 2010 income tax returns not initially completed by the giant tax preparation firm itself. If its pros at participating offices discover pay dirt — and they say they “recovered” $100,000 in overlooked credits and deductions during a recent roll-out in Detroit — they’ll tell you and even file the necessary IRS paperwork themselves for a minimal fee.

The idea is to help people get back their own money, says Elaine Smith, master tax advisor at H&R Block. No matter the amount, they could use the extra cash these days.

Among the most common errors unearthed during Detroit’s Second Look:

₪ Missed education credits. Actually, it wasn’t always just a matter of some people not knowing about the still-available American Opportunity Credit ($2,500 for the first four years of college education for each student), the Lifetime Learning Credit (up to $2,000 per return for post-secondary degree programs) and the Tuition and Fees Deduction (a reduction in taxable income of up to $4,000). In the case of 24-year-old Russell Gismonde, for instance, the part-time student and restaurant manager wound up $1,135 richer after H&R Block figured out he was personally better off claiming the Hope Credit than the Lifetime Credit he’d originally checked. (You can only pick one of these.)
“My plan is to have my own business someday,” says a grateful Gismonde, who’d always done his own taxes. “Every penny helps.”

₪ Inaccurate filing status. Don’t snicker. Understanding the financial implications of “married filing jointly” vs. “married filing separate,” say, isn’t a Detroit-only problem. Merely switching from one to the other meant a $5,498 refund for one family.

₪ Overlooked Earned Income Tax Credit. It’s supposed to incentivize employment among low-income earners, but not everyone knew they were eligible for the potentially thousands of dollars in credits.

With this year’s April 17 filing deadline looming, it could make sense to have past returns scoured before risking a replay of past blunders. If it’s easier, the review is accessible online using the Block Live video conferencing tool. 

Read More: 3 Tips to Help Small Businesses Save at Tax Time