George Michael secretly gave away millions — and didn’t want anyone to know.

The British singer-songwriter who first captured hearts with Wham! and later achieved worldwide success as a solo artist died on Christmas Day 2016. Known for his enduring hits and unmistakable voice, Michael also remained a fixture in the headlines for his often-public personal life.

While his public life was endlessly scrutinized, some of Michael’s most extraordinary deeds remained largely unknown. The late star, who would have turned 63 on June 25, is the subject of a new book, “Tonight the Music Seems So Loud.”

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Following George Michael’s death in 2016, the public learned the true extent of his quiet generosity. For years, he donated millions — often anonymously — to causes including children’s welfare, HIV/AIDS charities, homeless shelters and disadvantaged youth programs. He also funded IVF treatments, helped people in debt and supported countless individuals in need without seeking recognition. (Michael Putland/Getty Images)

“We will never know how much George Michael gave away because it was secret,” author Sathnam Sanghera told Fox News Digital. 

“He died with a net worth of around 97 million pounds (more than $128 million), but I suspect a lot of that money is still being given away by his estate. The estate releases annual statements about the donations it has made. So his good work continues.”

George Michael, left, and Paul McCartney, right, perform during the Live 8 concert in Hyde Park, London, on July 2, 2005. (AP Photo/Lefteris Pitarakis)

For Sanghera, Michael’s greatest achievement was compassion. Throughout his life, Michael frequently donated to charities supporting disabled children, cancer research, refugees and AIDS-related causes, just to name a few.

He began supporting charities as early as the 1980s while he was in Wham!, and his dedication continued for the rest of his life. As he quietly made large donations, Michael ensured they remained out of the public eye.

“Tonight the Music Seems So Loud: The Meaning of George Michael” by Sathnam Sanghera is available now. (Pegasus Books)

“George Michael was an incredible secret philanthropist, and the secrecy is what made it great,” Sanghera explained. “We’re only just finding out some of his charitable acts. For example, he gave away the first few years of royalties from ‘Last Christmas,’ one of the most successful pop songs of all time, to Band Aid, a U.K. charity aimed at combating hunger and poverty.”

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“He gave away the U.K. royalties from his ‘Best Of’ album in the 1990s,” Sanghera shared. “There are so many charities and individuals who have come forward to say, ‘He secretly paid for my IVF when he heard about my story on TV,’ for example.”

George Michael presents during the BRIT Awards held at the O2 Arena in London on Feb. 21, 2012. (Dave M. Benett/Getty Images)

Michael didn’t just give money — he gave his time. At a homeless shelter in London, he served food, sat with guests and listened to their stories. The book recounts how he would show up in jeans and a baseball cap, preferring anonymity to recognition. If someone commented that he resembled George Michael, he would chuckle and insist he got that comparison all the time.

George Michael and Andrew Ridgeley of Wham! perform in Japan in January 1985. (Michael Putland/Getty Images)

“His ex-boyfriend, Kenny Goss, has spoken about how he was given a job at every venue where George Michael played to identify a local charity and donate £20,000 to £30,000 to it,” Sanghera said. 

“Often, it had to do with children or nurses. And he would also invite the staff and beneficiaries of that charity to attend the concert. This is the way in which his philanthropy was routine as part of what he did day-to-day.”

George Michael and his partner Kenny Goss are seen here in Tokyo. (Nathan Shanahan/WireImage)

In 1990, Michael established the Platinum Trust, where, with the help of his sister Yioda, he supported disabled people. Michael donated royalties from his 1991 duet with Elton John, “Don’t Let the Sun Go Down on Me,” to the Terrence Higgins Trust, a London-based HIV awareness organization, The Associated Press reported, as cited by NPR.

Fans lay tributes of flowers, photographs and candles outside the home of pop music icon George Michael in The Grove, Highgate, on Dec. 28, 2016, in London. (Jack Taylor/Getty Images)

According to the outlet, proceeds from 1996’s “Jesus to a Child” went to Childline. The founder of the organization went on to tell the outlet that Michael donated millions of dollars over the years and urged everyone in the charity to keep his acts private. 

In 1999, when Michael performed at Net Aid to help refugees from Kosovo, he donated half a million pounds. Sanghera wrote that Michael was “annoyed” when the news leaked.

British singer-songwriter George Michael of Wham! sits in a Sydney hotel room during the pop duo’s 1985 world tour. (Michael Putland/Getty Images)

“There are so many stories about his generosity,” Sanghera told Fox News Digital. “There’s one story where his mother was sick with cancer at a local London hospital. After she passed, he put on a concert for all those nurses in the local community.”

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Princess Diana meets George Michael at the World AIDS Day annual “Concert of Hope” at Wembley Arena in London on Dec. 1, 1993. (Tim Graham Photo Library/Getty Images)

While his career soared and his personal life often played out in public, Michael continued supporting those in need.

“Along with Eric Clapton, he helped the family of Nigel Browne, a former bodyguard, win compensation after he was killed in a helicopter crash,” Sanghera wrote.

Linda Evangelista and George Michael pose during the “Too Funky” video shoot in Paris, circa 1992. (Kevin Mazur/Getty Images)

“He helped Martin Kemp, whom he set up with Shirlie Holliman, get life-saving treatment for a brain tumor. He played benefit gigs, raising money and awareness for famine relief, World AIDS Day, refugees, debt relief and Project Angel Food, which provides food to vulnerable Los Angeles residents suffering from critical and life-threatening illnesses.

George Michael and Elton John attend a gala dinner on behalf of AIDS victims at the Moulin Rouge in Paris on Oct. 11, 1994. (Stephane Cardinale/Sygma)

“… One time, studio colleague Johnny Douglas talked about how Michael not only allowed him to take a terminally ill child to his home in the south of France, but also provided a helicopter to pick them up and drop them off in the garden.

“He bought friends and relatives houses and cars in striking quantities, provided some with employment, and I lose count of the number of people I meet who tell me he paid for medical bills, funerals and housing in times of crisis,” Sanghera wrote. “On his death, his significant art collection was sold, raising more than £11 million for charity.”

George Michael performs on stage during his “Faith” tour at Earls Court Arena in London on June 15, 1988. (Pete Still/Redferns)

Sanghera told Fox News Digital he was stunned by the sheer amount of money Michael donated over the years. As he researched, he also lost count of the people who came forward with stories of how the singer had helped them behind the scenes, far from the public eye. Many of those stories poured in after Michael’s death.

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George Michael died of natural causes as the result of heart disease and a fatty liver, a British coroner announced in 2017. (Dave J Hogan/Getty Images)

“George Michael supported charities that weren’t necessarily glamorous for a pop star,” Sanghera said. “[Still], he gave away millions of pounds. His estate continues to support those charities in significant ways.”

In 1993, The Independent reported that Michael didn’t like to discuss his charity work. But that year, he was ready to talk, specifically about the charity album that he recorded for the Mercury Phoenix Trust, an AIDS-fighting organization founded in honor of Queen frontman Freddie Mercury.

George Michael died on Dec. 25, 2016, at the age of 53. (Sean Gallup/Getty Images)

“Everyone’s got really p—– off listening to celebrities patting each other on the back saying how generous they are being,” he told the outlet at the time. “And they are right to. The reason I am doing this interview is to support the Phoenix Trust. It’s very important these tracks get heard.”

George Michael walks over the red carpet before the screening of “George Michael – A Different Story” at the Berlin Film Festival on Feb. 16, 2005. (Michael Kappeler/DDP/AFP)

Sanghera stressed that Michael was no saint. But the evidence of his generosity is undeniable. And when it comes to the lives he touched, it’s easy to have faith.

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Singer George Michael leaves The Ivy restaurant in Hollywood on Dec. 7, 2001. (Scott Alfieri/Getty Images)

“He wrote a song called ‘Praying for Time,’ and there’s a lyric in that song where he complains about charity being ‘a coat you wear twice a year,'” Sanghera said. “… Charity means more when it is sincerely meant, when you do it without hoping to get anything out of it. And that’s what George Michael did.”