The Hollywood star's death was confirmed to the BBC by the office of Fred Mitchell, the Bahamas' minister of foreign affairs.
Poitier was a trailblazing actor and a respected humanitarian and diplomat. He won the Academy Award for best actor for Lilies of the Field in 1963.
Born in Miami, he grew up on a tomato farm in the Bahamas and moved to New York aged 16.
He signed up for a short stint in the army and did several odd jobs while taking acting lessons, en route to becoming a star of the stage and screen.
His appearance in The Defiant Ones in 1958 earned him his first Oscar nomination - in itself an historic achievement for a Black man in a lead category at the time.
Five years later he went one better, taking the glory for Lilies of the Field, in which he played a handyman who helps German nuns to build a chapel in the desert.
The actor was a regular on the big screen at a time of racial segregation in the US, appearing in a Patch of Blue in 1965, and then Heat of the Night the year after, followed by Guess Who's Coming to Dinner, playing a Black man with a white fiancée.
Guess who's coming to dinner?
Year : 1967 USA
Sidney Poitier, Katherine Hepburn and Spencer Tracy in a scene from Guess Who"s Coming to Dinner Photo: AFP/Columbia Pictures
Poitier picked his roles with care, burying the old Hollywood idea that Black actors could appear only in demeaning contexts as shoeshine boys, train conductors and maids.
In Heat of the Night he portrayed Virgil Tibbs, a Black police officer confronting racism during a murder investigation.
His other classic films included A Patch of Blue, The Blackboard Jungle and A Raisin in the Sun, which he also performed on Broadway.
He went on to direct a raft of films, and a Broadway play about his life and career was announced last month.
Empire magazine's Amon Warmann told the BBC: "He was a pioneer, he's so influential and paved the way for so many in the industry to make their own mark, not least Denzel Washington, who paid tribute to him when he won an Oscar."
(FILES) In this file photo taken on August 12, 2009, US President Barack Obama presents the Presidential Medal of Freedom to ambassador and actor Sidney Poitier during a ceremony in the East Room at the White House in Washington, DC. Former US president Barack Obama presents Sidney Poitier with the Presidential Medal of Freedom at the White House in August 2009. Photo: AFP
'Tackled racism head on'
Washington, who won an Oscar in 2002 on the same night Poitier won an honorary Oscar, joked as he said: "Forty years I've been chasing Sidney and what do they do - they go and give it to him in the same night."
Warmann added that Poitier "tackled racism head on" in his work but was also "so versatile".
"He really helped change the game for how black actors were viewed at that time [of his Oscar win]. He was one of the biggest stars during that period."
Star Trek actor George Takei paid tribute, calling the actor "a trailblazer who will be mourned by so many for whom he opened the very doors of Hollywood".
Dans la chaleur de la nuit
In the heat of the night
Real Norman Jewison
Sidney Poitier in a scene from In the Heat of the Night. Photo: AFP
James Bond and Westworld actor Jeffrey Wright added that Poitier was a "landmark actor".
Sidney Poitier. What a landmark actor. One of a kind. What a beautiful, gracious, warm, genuinely regal man. RIP, Sir. With love.
(Sam Falk/NYT) pic.twitter.com/5ZaKxxPdxw
— Jeffrey Wright (@jfreewright) January 7, 2022
Actress Whoopi Goldberg quoted the lyrics to the song To Sir With Love, which soundtracked Poitier's 1967 film. "He showed us how to reach for the stars," she noted, while actor Joseph Gordon-Levitt called him an "an absolute legend".
US broadcaster and journalist Oprah Winfrey put it to the actor an interview in 2000 that, as producer Quincy Jones had said, Poitier had "created and defined the African-American in film".
"It's been an enormous responsibility," Poitier replied. "And I accepted it, and I lived in a way that showed how I respected that responsibility.
"I had to. In order for others to come behind me, there were certain things I had to do."
Source _ BBC