Annie Ross was born Annabelle Allan Short on July 25, 1930, in Mitcham, Surrey, England, the daughter of the Scottish vaudevillians Jack and Mary Short; her brother was the entertainer and theatre director Jimmy Logan. She first appeared on stage at three. At four she crossed to New York with her family and won a token MGM contract in a children's radio contest run by the bandleader Paul Whiteman, after which her aunt, the singer and actress Ella Logan, took her to Los Angeles while her parents and brother went back to Scotland. As a child she sang in the 1938 short Our Gang Follies of 1938, played Judy Garland's sister in Presenting Lily Mars (1943), and at fourteen won a school songwriting contest with "Let's Fly," which Johnny Mercer and the Pied Pipers recorded.

After tenth grade she left school, took the name Annie Ross, and went to Europe, where she built her singing career. Based in Paris, she worked with American musicians who had settled there, among them James Moody, Kenny Clarke and Coleman Hawkins, and made her first record in Paris with Moody; her son Kenny Clarke Jr. (1950 to 2018) was fathered by Clarke. She returned to the United States in 1952. That year Bob Weinstock, who owned Prestige Records, asked her to write words to a jazz solo as King Pleasure had done, and she came back the next day with "Twisted," lyrics set to the tenor saxophone solo from Wardell Gray's 1949 recording of the same name. It was an underground hit and won her DownBeat's New Star award. Also in 1952 she made the Dee Gee EP The Voice of Annie Ross, with Milt Jackson, Percy Heath, Kenny Clarke and Blossom Dearie on piano. In 1953 she toured Europe with a Lionel Hampton band that included Clifford Brown, Art Farmer and Quincy Jones, then settled for several years in London, where she recorded Annie by Candlelight with the drummer Tony Crombie's quartet, appeared in the revue Cranks (1955, London and New York), and saw the BBC ban her 1956 record of "I Want You to Be My Baby" over a line in the lyric.

Back in New York in 1957, she was asked to coach a group of session singers who were recording vocal versions of Count Basie arrangements for Jon Hendricks and Dave Lambert. The singers could not make the music swing, and Lambert proposed that the three of them overdub every part themselves. The trio became Lambert, Hendricks & Ross, and their first album, Sing a Song of Basie (ABC-Paramount, recorded in 1957 and issued in 1958), made them an international act; it entered the Grammy Hall of Fame in 1998. They followed it with Sing Along with Basie (Roulette), made with the Basie band and the singer Joe Williams, The Swingers! with Zoot Sims (World Pacific), and, from 1959, three Columbia albums with the Ike Isaacs Trio: The Hottest New Group in Jazz, which includes a new version of "Twisted," Sing Ellington, and High Flying, which won the Grammy for best performance by a vocal group at the 1962 ceremony. In September and December 1961 they sang on The Real Ambassadors, the Dave Brubeck and Iola Brubeck jazz musical recorded with Louis Armstrong and Carmen McRae. Readers of DownBeat voted them best vocal group from 1959 to 1963. Alongside the trio she made her own albums for World Pacific, among them Annie Ross Sings a Song with Mulligan! with Gerry Mulligan, A Gasser! with Zoot Sims, and Gypsy, a set of songs from the Broadway show with Buddy Bregman's orchestra.

Heroin addiction, which she shared for a time with the comedian Lenny Bruce, wore on her in these years, and by 1960 the singer Carol Sloane was substituting for her on tour. After a London performance in May 1962 she stayed in England to deal with the addiction, and Yolande Bavan replaced her in what became Lambert, Hendricks & Bavan. In London she recorded Sings a Handful of Songs and Loguerhythms: Songs from the Establishment (a collaboration with the Tony Kinsey Quintet and the poet Christopher Logue) in 1963, married the actor Sean Lynch that year, and in 1964 opened a nightclub, Annie's Room, whose bookings included Joe Williams, Nina Simone, Stuff Smith, Blossom Dearie, Anita O'Day, Jon Hendricks and Erroll Garner. In 1966 she sang with Pony Poindexter and the Berlin All Stars at the Tenth German Jazz Festival in Frankfurt. Her singing work thinned in the 1970s, and she divorced Lynch and declared bankruptcy by 1975, but she found steady work as an actress: the film Straight On till Morning (1972), the stage Threepenny Opera (1972) and Side by Side by Sondheim, and the television series Charles Endell Esquire (1979). She also supplied the speaking voice of Britt Ekland in The Wicker Man (1973).

In 1981 she made In Hoagland with Georgie Fame, and in 1982 she was in Joe Papp's stage production of The Pirates of Penzance. Film roles followed, among them Superman III (1983), Throw Momma from the Train (1987), Pump Up the Volume (1990), and Robert Altman's Short Cuts (1993), in which she played the jazz singer Tess Trainer and sang. She moved to Los Angeles in 1985 and later back to New York, became a United States citizen in 2001, and returned to jazz clubs with the pianist Tardo Hammer and the bassist Neal Miner, appearing regularly at Manhattan's Metropolitan Room until it closed in 2017. She received the ASCAP Jazz Wall of Fame award in 2009, a National Endowment for the Arts Jazz Masters award in 2010, and a MAC Award for lifetime achievement in 2011. Her last album, To Lady with Love (Red Anchor, 2014), was recorded with Bucky Pizzarelli and John Pizzarelli. She passed away in New York City on July 21, 2020, of emphysema and heart disease, four days before her ninetieth birthday.

Ross is credited as a pioneer of vocalese, the setting of lyrics to recorded instrumental solos, and the critic Dave Gelly described her style as "a kind of dreamy watchfulness that is a definition of 1950s hip." "Twisted" remains her best-known example: a whimsical lyric about a patient's unraveling mind that satirizes psychoanalysis, set to a tenor solo, and later recorded by Joni Mitchell and Bette Midler among others. In Lambert, Hendricks & Ross she sang the high trumpet parts at the pace of the Basie band's soloists, with Jon Hendricks's lyrics and Dave Lambert's vocal arrangements written around the originals. She has said she could not read music but could sing down chord changes and reshape them, which is how she worked with her pianists, and that lyrics were always the easiest thing for her to memorize. The first record her aunt gave her, at about five, was Ella Fitzgerald's "A-Tisket, A-Tasket," and she has said that a record collection in her aunt's house introduced her to Billie Holiday. The vocalese tradition she helped establish is the one Amy London built her vocal quartet The Royal Bopsters around, and Ross sang as a guest on its 2015 debut. AllMusic's biography singles out her vocal dexterity and rich, clear tone, and her parallel career as an actress, in films, television and on stage, ran alongside her singing for decades.