PARTICIPATION NEEDS TO BE MANDATORY AND ENROLLMENT AUTOMATIC:

If someone handed you $1,300, would you turn it down?

One in four workers are essentially doing just that because they're not taking full advantage of their employer's 401(k) matching contribution. These workers end up leaving $24 billion on the table each year by not saving enough to get the full company match, according to a new report from Financial Engines.

For one person, that's like passing up on a $1,336 bonus.

"We're talking about real money here," said Greg Stein, director of financial technology at Financial Engines.

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