But wait, it gets worse. A millennial with $50,000 in student loan debt—not an unreasonable number, considering how much and how quickly these loans add up—will face retirement with close to $530,000 less than someone who has no loans.

So it should come as no surprise that millennials working on paying back those loans aren't contributing to retirement accounts at the same rate as peers who don't have to worry about those easy monthly payments. Millennials without student loans, the research found, are 60 percent more likely to maximize their employer match compared with those who are paying education loans.

Of course, it's easier to save for retirement when you're not paying off huge loans; your quality of life isn't quite so stripped of perks like dinners out or occasional vacations.

And that's another problem: millennials aren't willing to do without the little comforts of life, assuming they can afford them to begin with, just so that they can pay down loans and at the same time save for retirement.

A Schwab Retirement Plan Services study found that millennials aren't upping their savings rates if it means cutting out those little treats.

They might be sorry someday, though.

NerdWallet also crunched the numbers on how much student debt is costing millennials, and found that the class of 2015 won't be able to afford to retire till they're 75—and that carrying an average load of $35,051 in student loan debt and taking 10 years to pay it off will make them $684,474 poorer in retirement savings over 50 years.