The Badfinger original wasn’t released as a single, so most people weren’t familiar with it. Nilsson’s version, laced with lush orchestration, became a huge hit, climbing to #1 US in February 1972 and staying for four weeks. Nilsson was known as a songwriter and wrote most of the songs he recorded, but two of his biggest hits were covers: “Without You” and “Everybody’s Talkin’.”
“Without You” is not the kind of song Nilsson, who died in 1994, would have written. His compositions were far more acerbic, and he took pains to avoid the topic of love (or lack of it).
Nilsson first came across this song at a Laurel Canyon party in 1971 and thought it was a Beatles song. Badfinger was signed to Apple Records, The Beatles’ label, and their version of “Without You” was produced by Beatles associates Geoff Emerick and Mal Evans.
Nilsson also had a Beatles connection: John Lennon helped launch his career when he referred to Harry as his “favorite American group.” He and Lennon enjoyed a destructive time together from 1973-1975 that became known as the “lost weekend.”
Nilsson’s version added an orchestra and gave the song a dramatic production. When Nilsson recorded it, he initially played the song slow and dark, accompanied only by piano.
Producer Richard Perry recalled to Mojo magazine April 2008 that he had to persuade an unwilling Nilsson to record it as a big ballad: “I had to force him to take a shot with the rhythm section. Even while we were doing it, he’d be saying to the musicians, ‘This song’s awful.'” Songfacts.com