Schultz will keep the honorary title of chairman emeritus.
Starbucks Executive Chairman Howard Schultz on the USA economy, the impact of the tax reform legislation. The chain closed about 8,000 company-owned stores for an afternoon of anti-bias training last week, a decision that some shareholders questioned for the expense.
Following his transition off the Starbucks board at the end of June, Schultz will oversee the opening of the Starbucks Reserve Roastery in Milan on September 6 - marking the company's long-awaited entry into Italy - and the New York Roastery in late October.
Schultz at the opening of a Starbucks location in Tokyo on 2 August 1996.
In another twist, Schultz, 64, said he is considering the possibility of a 2020 presidential election run.
But when asked directly if he was thinking about running for president, he did not rule out the possibility. "For some time now, I have been deeply concerned about our country - the growing division at home and our standing in the world".More news: Sharapova thrashes Pliskova to set up potential Serena clash
The Seattle-based chain says he is writing a book about Starbucks' social-impact moves and its efforts to redefine the role of a public company.
Schultz, who has been openly critical of President Donald Trump, said "one of the things I want to do in my next chapter is to figure out if there is a role I can play in giving back".
More recently, as the company tried to restore its reputation after the arrests of two black men at a coffee shop in Philadelphia, Schultz said he didn't want people to feel "less than" if they were refused bathroom access.
In his letter, Schultz also credited the company with "balancing profitability and social conscience, compassion and rigor, and love and responsibility".
Starbucks' board named Myron Ullman, previously chairman and CEO of struggling retailer J.C. Penney Co, as its new chair, and Mellody Hobson as vice chair effective upon Schultz's retirement. Shares of Starbucks have risen 21,000 percent since the company's initial public offering in 1992; an investor who had put in $10,000 then would have more than $2 million today.