Elling was born in Chicago, Illinois, and raised in Rockford. He developed an early interest in music through the influence of his father, a kapellmeister at a Lutheran church. He sang in choirs and played several musical instruments. He encountered jazz while a student at Gustavus Adolphus College in Minnesota. After college, he enrolled in the University of Chicago Divinity School, but he left one credit short of a degree to pursue a career as a jazz vocalist. Elling was deeply influenced by singer Mark Murphy, and began to develop his idiosyncratic scat style in Chicago clubs, primarily at the Green Mill, sharing the stage with legends Von Freeman and Ed Peterson, and then played throughout the Midwest.
After sending a demo to Blue Note, Elling signed to the label and issued Close Your Eyes in 1995. He began to get attention from the jazz press, not only for his talent and original style, but also for his choice in sidemen, who included Laurence Hobgood and Paul Wertico for a time. His ultra-hip persona prevailed on 1996's Messenger, which was tougher and leaner than its predecessor, and along with hard touring and a taste for the theatrical and outrageous, Elling won over not only critics but jazz audiences from coast to coast. He was married that same year and chose, depending on your point of view, either to revise his hipster image or broaden his traditional base with a collection of standard ballads and love songs entitled This Time It's Love. The album won numerous awards in magazines and was nominated for a Grammy.
He also re-emerged with his own album, The Gate, in 2011. The set was produced by Grammy winner Don Was. Easily his most provocative offering, it featured a few modern jazz standards juxtaposed against a slew of pop, rock, and soul tunes that were radically rearranged and performed by an all-star band that included Hobgood, John Pattitucci, and Bob Mintzer, to mention a few. The following year, Elling issued 1619 Broadway: The Brill Building Project, which paid homage to the classic American pop music that emanated from the iconic Brill Building during the '50s and '60s.
The singer's 11th studio album, 2015's Passion World, found him exploring compositions and musical styles from around the globe. In June of 2016, Elling paired with saxophonist Branford Marsalis for the sophisticated quartet date Upward Spiral. That October, he returned with The Beautiful Day: Kurt Elling Sings Christmas, his first ever holiday-themed collection. In 2018, he again collaborated with Marsalis on The Questions, covering songs by a varied group of composers, including Paul Simon, Bob Dylan, and Leonard Bernstein. Joining them were pianist Joey Calderazzo, trumpeter Marquis Hill, drummer Jeff "Tain" Watts, and others. While the title referred to philosophical and metaphysical conisderations, its popular appeal was clear; it peaked at number five on the Jazz Albums charts. Elling followed the date with a live version of the album backed by his own band. In 2019, Elling issued Live in New York, co-billed to Australian trumpeter James Morrison. The set also featured pianist Stu Mindeman, saxophonist Troy Roberts, bassist Clark Sommers, and drummer Ulysses Owens, Jr.