The Duke of Sussex's memoir will be published on 10 January, his publisher Penguin Random House has said.
The book by Prince Harry will be titled Spare and will include his full account behind his decision to give up royal duties and move to the US.
Random House said: "As Diana, Princess of Wales, was laid to rest, billions wondered what the princes must be thinking and feeling - and how their lives would play out...
"For Harry, this is his story at last."
Buckingham Palace said it would not comment on the book announcement.
Some of the proceeds from the book will be used to support British charities, including Sentebale and WellChild. The publisher confirmed this was in the form of two donations of $1.5m and £300,000 respectively to the two named charities.
When the deal for Prince Harry to write his story was announced in 2021, the prince promised he would reflect "the highs and lows" and be "accurate and wholly truthful".
That theme is picked up in the publicity statement for the book, which says: "With its raw, unflinching honesty, Spare is a landmark publication full of insight, revelation, self-examination, and hard-won wisdom about the eternal power of love over grief."
The book will be published on the same date worldwide and it will be available in 16 languages.
The Duke and Duchess of Sussex announced that they would step back from royal duties and work to become financially independent in 2020. At the time, Buckingham Palace and senior royals expressed their disappointment and hurt by the announcement.
Harry and Meghan now live in the US with their two children, son Archie and daughter Lilibet.
The publisher's description of the book's author, which is likely to appear in the book, reads: "Prince Harry, the Duke of Sussex, is a husband, father, humanitarian, military veteran, mental wellness advocate, and environmentalist. He resides in Santa Barbara, California, with his family and three dogs."
Source: BBC
Image source: AP
