U.S. Secretary of Education Betsy DeVos reads a book to elementary students in Prince William County, Virginia.

Unlike her predecessors, Education Secretary Betsy DeVos does not fly commercial airlines when she travels on the job. Instead, she takes her own private plane — and never bills the government, according to a spokeswoman.

“Secretary DeVos travels on personally owned aircraft, accompanied by her security detail and whenever possible, additional support staff, at zero cost to U.S. taxpayers,” spokeswoman Elizabeth Hill said. “The secretary neither seeks, nor accepts, any reimbursement for her flights, nor for any additional official travel-related expenses, such as lodging and per diem, even though she is entitled to such reimbursement under government travel regulations.”

The travel of President Donald Trump’s Cabinet members has come under scrutiny after reports about their use of noncommercial flights for travel at immense cost to taxpayers. DeVos has also faced criticism over her high-priced security detail: She is the only Cabinet member to get protection from the U.S. Marshal’s Service at a cost of nearly $8 million over eight months.

The U.S. Treasury’s Office of the Inspector General is looking into travel by Treasury Secretary Steven Mnuchin and his wife, Louise Linton, who used a government plane on a trip that involved viewing the solar eclipse. Mnuchin also requested a military aircraft to fly him to his European honeymoon over the summer, but was denied.

Politico reported this week that Health and Human Services Secretary Tom Price used chartered flights to travel to New Hampshire and Philadelphia, which cost tens of thousands of dollars more than commercial flights.

But DeVos has billed the government only once for travel since she took office — $184 for a round-trip Amtrak ticket to Philadelphia. Hill said DeVos plans to donate her government salary.

“Secretary DeVos accepted her position to serve the public and is fully committed to being a faithful steward of taxpayer dollars,” Hill said.

DeVos comes from immense family wealth: Her father, Edgar Prince, ran a successful business delivering auto parts to manufacturers and her husband, Dick Devos Jr., is an heir to the Amway direct-sales fortune. She has directed much of her personal wealth to advocating for school choice and private school vouchers.

Her predecessor, John King Jr., spent $39,000 on travel, according to records, and about $28,000 on flights during his first six months on the job. In an interview with The Washington Post, he said he always flew “on regular commercial flights” when he traveled and typically flew coach.

“Always coach, although occasionally I’d upgrade if there was a blessing from the frequent flyer gods,” King said.

Arne Duncan, who was education secretary from 2009 to 2016, also flew commercial, according to a former spokesman.

“We always flew commercial and always on the most economical fare. Arne — who is over 6 feet tall and probably could have used the upgrade for the leg room — insisted on sitting in economy class with everyone else,” said Justin Hamilton, who left the department in 2012.

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