The song, a cover of Simon and Garfunkel's "Bridge Over Troubled Water", also features performances from Leona Lewis, James Blunt and a large choir made up of local people, some of whom survived the blaze.
A total of 79 people died in the fire, which swept through the 24-storey Grenfell tower on June 14th. Many people are still unaccounted for and authorities have suggested that the death toll will continue to rise as rescue workers continue to search.
The single is an initiative of pop impresario and TV talent show judge Simon Cowell.
In a departure from the original version of the song, Cowell's version opens with grime artist Stormzy rapping: "That could have been me up there / waving my white plain tee up there", a reference to people trapped in the blaze.
Reaction to the song on social media was generally positive, with Twitter user Sarah Styles saying the song was "absolutely beautiful", while user Amy Elizabeth said the song left her "covered in goosebumps".
The song was made available for sale and radio play on Wednesday and Cowell tweeted that a video would premiere on British television that evening. All proceeds from the song are to go to the London Community Foundation. (Writing by Mark Hanrahan in London; Editing by Raissa Kasolowsky)