We know that the Duke of Sussex is releasing a memoir—but what is Prince Harry’s book salary, exactly? Well, according to new reports, the California-based royal is earning anywhere between $15 to $20 million from his advance alone.

Sources who spoke to Radar Online on Tuesday, July 20, claimed that the Duke of Sussex, 36, is making $15 million from his advance. But this hefty paycheck isn’t just thanks to him being a high-profile name; according to the insider, this sum is reflective of the publisher’s expectation that he tells all in this new memoir. “This book is going to make the Oprah interview look like the tip of the iceberg,” the source explained. “Harry is not getting a $15 million advance just because of who he is, he is getting it because he is going to tell everything.”

A publishing source added, “There has never been a royal book like this before. There is no prototype or sale numbers to base the value of this book on.”

The New York Post’s Page Six also reported that the Duke of Sussex is earning millions from his memoir. The site’s estimate for his advance was higher than Radar’s at around $20 million. Meanwhile, Harry’s co-writer, J.R. Moehringer, is expected to make at least $1 million, as per Page Six.

News of Harry’s memoir first broke on Monday, July 19. The Duke of Sussex confirmed the news in a statement via PEOPLE. “I’m writing this not as the prince I was born but as the man I have become. I’ve worn many hats over the years, both literally and figuratively, and my hope is that in telling my story — the highs and lows, the mistakes, the lessons learned — I can help show that no matter where we come from, we have more in common than we think,” his statement read.

He added, “I’m deeply grateful for the opportunity to share what I’ve learned over the course of my life so far and excited for people to read a firsthand account of my life that’s accurate and wholly truthful.”

The “intimate and heartfelt” memoir, which is scheduled to be released in late 2022 via Penguin Random House, is said to focus on “his lifetime in the public eye from childhood to the present day, including his dedication to service, the military duty that twice took him to the frontlines of Afghanistan, and the joy he has found in being a husband and father,” according to a blurb from the publisher.

As we previously reported, “chaos” allegedly erupted at Kensington Palace following the news of Harry’s memoir. An insider told Page Six on Monday that Harry’s father, Prince Charles, was “surprised” by the book. Sources claimed at the time that Harry had not told his family about the book before its announcement, though a spokesperson for the Duke of Sussex later denied this report.

Nevertheless, both Harry’s brother William and Charles were still “shaken” by the news, according to Us Weekly. “The royal family is shaken up about the book,” the source told the site. The insider added that William and Charles are “particularly concerned about what Harry will reveal” after Harry’s recent interviews about the royals, which were already “bad enough.”