Bradley Cooper said that Lady Gaga was the one who convinced him they should sing live. Gaga said she hated watching movies where the actors were not lip-syncing correctly to the songs, and to avoid this and get it right they needed to sing live for the film. This caused Cooper to get more extensive vocal training.
Like his character Jackson, Bradley Cooper dealt with both alcohol and drug addiction. He has spoken publicly about how sobriety saved both his life and career.
Some of the scenes were filmed at the Coachella Festival in 2017, where Lady Gaga was the first female headliner in ten years. Festival-goers paid ten dollars to see the scenes being filmed, although recording devices were locked away to prevent any footage from being leaked.
Sam Elliott claimed the scene of Jackson and Bobby getting in a fight was his first scene filmed. Inspired by starting off with such an intense scene on his first day, Elliott decided to play up Bobby's raw heartbreak at his brother. The tears were unscripted.
For his role as Jackson Maine, Bradley Cooper was taught to play guitar by Lukas Nelson, son of Willie Nelson. The pair hung out in Cooper's basement almost every night for a year so that Cooper could learn how to perform and present himself like a musician. Cooper is backed by Lukas Nelson & Promise of the Real for his stage performances. Veteran dialect coach Tim Monich worked for several months with Cooper to help him better flesh out his vocal singing range.