James George Hunter was born August 19, 1918, in Spokane, Washington, and took the name Jimmy Rowles professionally (he spelled it "Jimmie" on many record sleeves and used both forms his whole life). He grew up on South Tekoa Street near Manito Park, was a serious competitive tennis player as a teenager, and taught himself piano well enough to be working the Davenport Hotel in Spokane by 1934, reportedly showing up for the job in tennis shoes. He attended Gonzaga University in his home city, then moved to Los Angeles in 1940 to play with small groups. In 1942 he joined Lester Young's band, the connection that put him inside the circle he would work in for the next fifty years. He married Dorothy Paden and they had three children: Stacy, who became a jazz trumpeter and flugelhornist; Stephanie; and Gary, who played guitar with Eric Burdon and with Arthur Lee's band Love.

Army service in the Second World War interrupted the run. Afterward Rowles took the big-band chairs that were the standard path for a working Los Angeles pianist, playing and recording with Woody Herman (1946-1947), Benny Goodman (whose small groups he appeared with repeatedly between 1948 and 1956), Les Brown, and Tommy Dorsey. He then settled into the Los Angeles studios, where he stayed busy for roughly two decades. His piano turns up on Henry Mancini's Experiment in Terror (1962), Charade (1963), and The Pink Panther (1963), on the 5th Dimension's Stoned Soul Picnic (1968), on Gerald Wilson's California Soul (1968), and, at length, on the DePatie-Freleng cartoon series The Ant and the Aardvark (1969-1971).

The studio work paid, but the reputation came from what he did behind singers. Rowles played on Billie Holiday's Verve sessions of the mid and late 1950s, including Music for Torching (1955) and Songs for Distingué Lovers (1957), and backed Peggy Lee through the same period, notably on Black Coffee (1953). He recorded four albums with Julie London between 1957 and 1960, accompanied Carmen McRae on her 1972 Atlantic live album The Great American Songbook, and was co-billed with Sarah Vaughan on Sarah Vaughan & The Jimmy Rowles Quintet (Mainstream MRL 404, 1974). McRae called him "the guy every girl singer in her right mind would like to work with." His association with Ella Fitzgerald ran even longer: he played behind her at the Mocambo in Hollywood in late 1956, appeared on her sessions through the 1960s, and in 1981 succeeded Paul Smith as her regular accompanist for close to three years, including her 1982 Nelson Riddle collaboration The Best Is Yet to Come. "Baby, Don't You Quit Now," which Rowles wrote with Johnny Mercer, closed out that relationship on Fitzgerald's final album, All That Jazz (1989).

His own leader catalog started early and stayed small until the 1970s. Rare, But Well Done (Liberty LRP 3003), a trio date with Red Mitchell and Art Mardigan cut in Hollywood in 1954 for producer Harry Babasin, went out on Liberty that same year in Canada and in 1955 in the United States. A 1957 sextet album for Tampa, Let's Get Acquainted With Jazz ...For People Who Hate Jazz!, put him with Harold Land, Pete Candoli, Barney Kessel, Mitchell, Larry Bunker, and Mel Lewis; Interlude reissued it in 1959 under the better-known title Upper Classmen. Weather in a Jazz Vane (Andex, 1959) expanded the group to a septet with Herb Geller, Lee Katzman, Bob Enevoldsen, and Monty Budwig, produced by Bill Holman. Against all that West Coast activity, Rowles was also the pianist on Pepper Adams's leader debut, Critics' Choice, recorded August 23, 1957, for World Pacific (PJM-407) with Katzman, Doug Watkins, and Lewis: a Detroit-bred baritone player's hard bop program handed to a Los Angeles rhythm section. There were a few more one-offs (a 1960 Broadway-songs album for Signature, the vocal-heavy Kinda Groovy! for Capitol in 1962, a 1968 trio session issued decades later as Our Delight), but for most of the 1960s he was a studio player first.

Moving to New York in 1973 changed that. Over the next decade Rowles made more records under his own name than in the previous twenty years. The Special Magic of Jimmy Rowles (Halcyon, 1974) was taped live in a Manhattan apartment on April 7, 1974, with Alec Wilder supervising. In March 1976 a single stretch of sessions for the Choice label with Buster Williams and Billy Hart produced two albums, Grandpaws and Paws That Refresh. Stan Getz produced and played on The Peacocks (Columbia JC 34873), recorded in New York in 1975 and released in 1977, an album built around Rowles's own title tune and featuring Buster Williams and Elvin Jones. Xanadu got two dates out of him, Heavy Love with Al Cohn (March 15, 1977) and the trio We Could Make Such Beautiful Music Together (April 4, 1978). For Pablo he made two albums with Zoot Sims and George Mraz, If I'm Lucky (October 1977) and Warm Tenor (September 1978), and for Concord two piano-and-bass duo records with Ray Brown, As Good As It Gets (1978) and Tasty! (1980). A single day in Paris, July 21, 1978, at the Studio des Champs-Elysées yielded material for three separate French LPs: the solo Scarab and Nature Boy, and the duo Red'n Me with Red Mitchell.

Rowles returned to Los Angeles in 1983, after the Fitzgerald tours ended, and kept working steadily. Columbia recorded him solo on Jimmy Rowles Plays Duke Ellington and Billy Strayhorn (1981); Pablo paired him with Joe Pass for Checkmate, cut in a single January 12, 1981, session in Venice, California; and Pepper Adams brought him to Van Gelder Studios on September 30, 1981, for Urban Dreams (Palo Alto PA 8009), a quartet with Mraz and Hart that critics rate among Adams's strongest leader dates. The last decade of his career is full of family records: Tell It Like It Is (Concord, 1984) and Looking Back (Delos, 1989) with his daughter Stacy on trumpet and flugelhorn, and the Contemporary quartet album I'm Glad There Is You, recorded direct to two-track digital at Fantasy Studios in Berkeley in March 1985 with Red Mitchell and Stacy. In 1983 he also spent time in Los Angeles coaching a young Diana Krall, sharpening her playing and pushing her toward singing. Los Angeles declared September 14, 1986, "Jimmie Rowles Day." He made Lilac Time at Capitol Studio B in April 1994 with Herbie Mann producing, and in 1995 accompanied singer Jeri Brown on A Timeless Place, an album drawn entirely from his own compositions. Jimmy Rowles suffered cardiac arrest and passed away in Burbank, California, on May 28, 1996, at 77.

Rowles built his style out of the swing-era vocabulary he learned behind Lester Young and Benny Goodman, then bent it toward the harmonic language of Duke Ellington and Billy Strayhorn, whose ballads he returned to obsessively: "Blood Count," "Isfahan," "Lotus Blossom," and "Lush Life" recur across his leader dates, and he devoted a whole 1981 Columbia solo album to the two composers. What set him apart from the other West Coast pianists of his generation was restraint used as a tool rather than a limitation. He played sparely and off the beat, voiced chords low and close, left holes for a singer to move through, and dropped in oblique substitutions that reframed a standard without ever crowding it, which is why so many vocalists preferred him over flashier accompanists. His own writing had the same sideways quality. "The Peacocks," a slow, harmonically ambiguous piece that resists a fixed key center, became his signature, recorded by Stan Getz on the 1977 Columbia album named for it, later by Bill Evans, John McLaughlin, Esperanza Spalding, and others, used in the soundtrack to Bertrand Tavernier's Round Midnight (1986), and given lyrics by Norma Winstone under the title "A Timeless Place." His 1958 blues "502 Blues (Drinkin' and Drivin')" reached a wider audience through Wayne Shorter's 1966 Blue Note recording on Adam's Apple and ended up in the Real Book. He sang too, in a dry, cracked half-spoken voice that he used sparingly and to real comic effect on records like Kinda Groovy! and Isfahan.