The 401(k) is among the most important retirement savings vehicles.
Direct 15% of your annual income to a 401(k), according to Kelly Lannan, director of personal investing at Fidelity Investments.
"That includes both what you yourself are putting in, as well as if you're taking advantage of that employer match," she said.
Consumers can contribute a maximum of $18,500 to their 401(k) in 2018.
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