Most Americans have trouble saving money. The overall personal savings rate came in at 7% of income in 2018, according to Federal Reserve data, and 40% of Americans say they wouldn't have the cash on hand to deal with an unexpected expense of just $400.

"Most," however, is by no means "all": TD Ameritrade recently conducted a study that dug into the behaviors and habits of a demographic the researchers dubbed "super savers" -- Americans who save more than 20% of their annual income. Perhaps unsurprisingly, members of this group approach financial matters somewhat differently than the rest of us.

"The biggest difference between super savers and others is simply the amount they save -- on average, 29% of their income, compared to non-super savers, who save 6%," said Dara Luber, senior manager of retirement at TD Ameritrade in a press release. "Three in four super savers are financially independent, or on the path to be, compared to less than half of non-super savers, with more of them heading toward early retirement."

A person drops change itno a piggy bank.

Saving money requires sacrifices. Image source: Getty Images.

What do super savers do?

More than half (54%) of super savers start investing by the age of 30, with 30% starting by age 25. That compares to 39% by 30 and 20% at 25 among the other respondents.

In fact, only 4% of them said they don't invest at all, compared 23% of non-super savers. And 57% of super savers plan to retire earlier than their parents did (or they've already done so), compared to 46% of non-super savers.

But it's not just saving more that sets them apart. They are also spending less than the average American in nearly every category. The biggest differences are in housing (14% of income versus 23%) and household expenses (16% of income versus 21%).

The vast majority of super savers surveyed (88%) said that it's worth making sacrifices now to achieve financial independence sooner. There were four key metrics uncovered by the survey that showed significant differences between super savers and the rest of us.

  • 65% avoid high-interest debt, compared to 56% of others;
  • 60% stick to a budget, compared to 49% of others;
  • 58% invest in the stock market, compared to 34% of others;
  • 55% max out their retirement savings contributions, compared to 30% of others.

"The good news is that the tools and practices these super savers are employing to pursue their financial goals are available to all Americans," said Luber. "Low- and no-fee ETFs, brokerage accounts with low or no trading fees, retirement accounts, and other investment vehicles are widely available, and it's never too late to set up a budget or start investing."

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What can you do?

Saving and spending are naturally intertwined. To increase your savings, you must either spend less or make more. Ideally, you will target a percentage of income to set aside and invest, and keep saving at that rate as your income grows.

It's a strategy that requires sacrifice. Buying a smaller house, renting a less desirable apartment, or keeping your car for many years after you pay it off are the kind of decisions that can lead you to financial independence sooner.

Finally, it's important to set some clear financial goals. Any time you want to stay consistent about foregoing certain types of immediate gratification, it's good to be able to focus on your longer-term reasons. With those in mind, you have a much better shot at staying prudent now, and setting yourself up for a comfortable future.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.