Robbert JF de Klerk, managing partner of the Humphrey Bogart Estate, said Bacall died yesterday at her home in New York. A family member told entertainment website TMZ that the actress had a massive stroke.
Her films included How To Marry A Millionaire, The Mirror Has Two Faces, The Big Sleep and Designing Woman, but one of her biggest was with Bogart - Key Largo, in 1948.
She married Casablanca star Bogart in 1945 and the couple remained together until his death in 1957.
Bacall married actor Jason Robards in 1961 but they divorced in 1969.
The actress, who had three children, appeared recently on an episode of the US animated sitcom Family Guy as Evelyn, a friend of Peter's mother.
Sultry-voiced Bacall became famous with her first movie scene, opposite Bogart in 1944's To Have And Have Not. The willowy 19 year old famously said: "You know how to whistle, don't you, Steve? You just put your lips together and blow."
She was nominated for an Academy Award, won two Tony Awards and received an honorary Oscar in 2009.
She was among the last of the old-fashioned Hollywood stars and her legend, and the legend of "Bogie and Bacall" - the hard-boiled couple who could fight and make up with the best of them - started almost from the moment she appeared on screen.
The fashion model and bit-part New York actress before moving to Hollywood was less than half Bogart's age, yet as wise and as jaded as him. Her sly glance, with chin down and eyes raised, added to her fame; she was nicknamed "The Look".
Bogart and Bacall co-starred in three more films after To Have And Have Not - The Big Sleep (1946), Dark Passage (1947) and Key Largo. Their marriage lasted until his death from cancer.
She appeared in movies for more than half a century, but not until 1996 did she receive an Oscar nomination - as supporting actress for her role as Barbra Streisand's mother in The Mirror Has Two Faces. Although a sentimental favourite, she lost to Juliette Binoche for her performance in The English Patient.
She finally got a statuette in November 2009 when she was presented with a special Oscar at the movie academy's new Governors Awards gala.
"The thought when I get home that I'm going to have a two-legged man in my room is so exciting," she quipped.
Bacall was always a star. With her lanky figure and flowing blonde hair, she was seemingly born for check suits and silk dresses. On television talk shows, she exhibited a persona that paralleled her screen appearances.
She was frank, even blunt, with an undertone of sardonic humour, all of which she demonstrated in her best-selling 1979 autobiography By Myself. She published an updated version in 2005, By Myself And Then Some, noting that as she ages, "I don't feel that different. But I sure as hell am".
When her movie career faded, she returned to the theatre. She starred in the hit comedy Cactus Flower and stepped lively in Applause, a musical version of the classic movie All About Eve that brought her first Tony in 1970.
She got the second Tony in 1981 for Woman Of The Year, based on a film that starred her idol Katharine Hepburn. She enjoyed another triumph in London with Sweet Bird Of Youth, in 1985.
She was ever protective of the Bogart legacy, lashing out at those who tried to profit from his image. In 1997 she appeared at the Chinese Theatre in Hollywood for ceremonies launching the US Postal Service's Humphrey Bogart stamp.
When the American Film Institute compiled its list of screen legends in 1999, Bacall ranked No 20 on the roster of 25 actresses. Bogart topped the list of actors.
"She was sexy, she was saucy and she projected a sense of intelligence," said film historian Leonard Maltin. "And amazingly, she was doing all that when she was barely 20 years old."
Here are 10 key roles in Lauren Bacall's long career, in film and on stage.
TO HAVE AND HAVE NOT (1944): Bacall's film debut, made when she was 19, and of course, her first film with Humphrey Bogart. The two fell in love on set. And if that were not enough to immortalise the movie, there was the classic line, delivered by Bacall: "You know how to whistle, don't you Steve? You just put your lips together and ... blow." Director Howard Hawks wisely mined the chemistry between these two actors.
THE BIG SLEEP (1946): By the time this film noir was made, Bacall and Bogart were married. Hawks also directed this one, an adaptation of Raymond Chandler's 1939 detective story. Despite what was seen as a terribly confusing plot, the film capitalised on the public fascination with the screen couple.
KEY LARGO (1948): Also a film noir, and also starring Bogart - along with Edward G Robinson, Lionel Barrymore and Claire Trevor. The movie, directed by John Huston, was the last of four Bacall did with her husband (the third was Dark Passage). Inspired the 1981 song Key Largo by Bertie Higgins.
HOW TO MARRY A MILLIONAIRE (1953): A light-hearted comedy that teamed Bacall with Marilyn Monroe and Betty Grable; the actresses played models aiming to land rich husbands. Also a great one for quotes. "You don't think he's a little old?" Bacall's character, Schatze Page, is asked. "Wealthy men are never old," she replies.
DESIGNING WOMAN (1957): Another romantic comedy, this time with Bacall starring opposite Gregory Peck. Bacall played a fashion designer, Peck her sports writer husband. The film did well, but Bacall was going through personal turmoil; Bogart died of cancer several months before the film's release.
APPLAUSE (1970): Appearing on Broadway, Bacall won a best-actress Tony for her performance as Margo Channing in this musical, based of course on the 1950 Bette Davis film All About Eve.
MURDER ON THE ORIENT EXPRESS (1974): An older Bacall played a brash, widowed American socialite in this popular Agatha Christie adaptation in which everyone was a suspect.
WOMAN OF THE YEAR (1981): Bacall won her second Tony in this John Kander and Fred Ebb musical, also based on a classic film: the 1942 movie of the same name starring Katharine Hepburn and Spencer Tracy.
THE MIRROR HAS TWO FACES (1996): Bacall played Barbra Streisand's vain, obnoxious mother - and scored an Oscar nomination for best supporting actress.
DOGVILLE (2003): Bacall starred with Nicole Kidman in this Danish drama by Lars von Trier about a young woman (Kidman) hiding out in a small town in Depression-era Colorado.