A snippet of the song was featured in first official tailer of A Star Is Born. The trailer ends with Jackson (Bradley Cooper) pushing Ally (Gaga) on a stage to perform "Shallow".
SPOILER ALERT! At least some content in this article contains spoilers.
The power ballad is the first song Lady Gaga's Ally and Bradley Cooper's Jack sing together in the film. In her interview on Zane Lowe’s Beats 1 Radio premiering "Shallow", Gaga explained:
I worked on Shallow with Mark Ronson and Andrew Wyatt and Anthony Rossomando and we made this song for Ally and Jack and it’s such a special song. It’s two people talking to each other about the need and the drive to dive into the deep end and stay away from the shallow area. We were writing 'Shallow' from the point of view of Ally, it becomes part of the reason they fall in love. When I was writing music for the film I had to think about Ally as if she wasn't me. I went with a sound for her, even in the pop realm, that's unlike anything I've ever put out before.
Gaga announced the release date of the single a day before its release on social media. The track was premiered on September 27, 2018 as Zane Lowe's "World Record" on Beats 1 radio.