When it comes to investing, the biggest mistake women make has nothing to do with where they're choosing to invest their money — in fact, women tend to earn higher returns than men.
Rather, the issue is they're not investing enough in the first place, says Sallie Krawcheck, co-founder and CEO of Ellevest, a digital investment platform for women.
"We certainly don't invest as much as men do, " Krawcheck tells CNBC Make It. "We tend to leave more than 70% of our wealth in cash as opposed to investing it. For the typical professional woman, that can cost her hundreds of thousands — for some women, millions — of dollars over the course of their lives."
Not putting their money to work can be "a bigger drain on their net worth than the gender pay gap," Krawcheck adds.
That's why her No. 1 piece of financial advice for women is to simply start investing. Ellevest, the robo-advisor that Krawcheck founded in 2014 to help close the gender investing gap, makes it easy to do so — there's no minimum required to open an account. Here are some other low-stress ways to dip your toe in investing:
Regardless of where you decide to invest your money, start today. The longer you wait, the more you'll miss out on compound interest, which will help your wealth grow so you can save hundreds of thousands or even millions of dollars.
More from Invest in You:
Women must keep finding ways to avoid the 'money FOG'
The financial lessons this mother of two learned after suffering an unimaginable loss
Jean Chatzky: Here's how women can take control of their finances
As Krawcheck puts it: "A dollar invested in your 20s is worth more than a dollar invested in your 30s is worth more than a dollar invested in your 40s is worth much more than in your 50s, 60s or 70s. "
Disclosure: NBCUniversal and Comcast Ventures are investors in Acorns.