This story is part of a MarketWatch series, “Gifts that pay off,” that have a larger impact long after the holiday season has passed.

Millions of Americans will open their wallets for good causes during the holiday season, but like most money-related activities, the rich do their charitable giving differently than average Americans. Here’s a look at how wealthier Americans give to charity:

They don’t only do it for the tax break

Contributions to nonprofits are generally tax deductible, which means they can lower their annual tax bill — though they do have to itemize donations to get the tax break. Some critics argue that wealthier families get more benefit from that part of the tax law.

But it’s actually not much of a factor when wealthy people are deciding whether to give, according to the 2018 U.S. Trust Study of High Net Worth Philanthropy. Just 17% of wealthy donors said they were always motivated to give by tax benefits, and 51% said that was “sometimes” a reason.

Most — 93% — said they give because they believe their gift can make a difference. “Tax benefits are really not a primary motivation for giving,” said Gillian Howell, managing director of U.S. Trust’s philanthropic solutions group. “They’re giving much more for altruistic reasons.”

They plan to give more next year

That’s good news for nonprofits who have been worried that the new tax law — which doubled the standard deduction — could lead to a big drop in donations if fewer people itemize.

In fact, only 10% of donors across all income levels said they plan to give less this year, and most wealthier donors (74% of those with annual incomes of more than $150,000) say they’ll give more in 2018 than they did in 2017, according to a recent survey by online fundraising platform Classy.

Of course, charitable giving tends to be fueled largely by stock-market performance, so donors may change their plans if markets suffer prolonged losses.

As the 2018 Giving USA report noted, “Research has found a statistically significant correlation between changes in total giving and values on the Standard & Poor’s 500 Index SPX, -1.74% Because stock-market values are an indicator of financial and economic security, households and corporations are more likely to give when the stock market is up.”

They’re more likely to volunteer

Cash isn’t the only way people give to charity; they also donate their time and talents. Wealthier people are more likely to do so than the average American. Some 48% of high net worth people donated their time in 2017, compared to 25% of the general population, the U.S. Trust study found. One theory: They may be more likely to afford child care and, as such, have more free time.

The average net worth of respondents in the U.S. Trust Study was $16.8 million. The study, a partnership with Indiana University Lilly Family School of Philanthropy, was based on a survey of 1,646 U.S. households with a net worth of $1 million or more (excluding the value of their primary home) and/or an annual household income of $200,000 or more.)

Women lead the way

Wealthy women are more likely to give to charity than their male counterparts: 93% of wealthy women donated last year, compared to 87% of wealthy men. They’re also more likely to volunteer, the U.S. Trust study found. Researchers didn’t compare wealthy women’s giving habits to those of average-income women, but Howell said the gender disparity probably applies across income levels.

Higher education is a favorite cause

“Colleges and universities received the second-highest share of the $14.7 billion that America’s wealthiest donors contributed to charity in 2017 at $1.8 billion,” the 2018 Giving USA report found, citing the Chronicle of Philanthropy. That puts some schools on an enviable list: America’s top 10 favorite charities in terms of cash support in 2016 included Harvard University (No. 4), Stanford University (No. 6) and Cornell University (No. 10), the Chronicle reported.

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Among donors of all income levels, the top cause in 2017 was religion, followed by education and human services, according to Giving USA.

Globally, about one-third of all “ultra high net worth” individuals give to education, making it the most popular cause among the affluent, according to the 2018 World Ultra Wealth Report by WealthX, which looked at households with $30 million or more in net worth.

See also: American donations to charity show widening gap between rich and poor

Wealthy millennials don’t donate as much

Affluent millennials are less likely than their older wealthy peers to make direct cash contributions to charities, the 2018 Giving USA report found. They tend to consider their entire lifestyle — from the products they buy to the jobs they take — as an opportunity to act charitably, said Una Osili, the associate dean for research and international programs at Indiana University’s Lilly Family School of Philanthropy. Osili was a co-author of the Giving USA report. Supporting a businesses that has a social justice mission may count as a charitable endeavor to them, she said.

“The perception is that millennials are very generous and engaged in social causes, but millennials define giving very differently,” Osili told MarketWatch. “For example, supporting a businesses that has a social justice mission for them could be charitable.”

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