The first look poster of the film was unveiled Saturday.
In the poster, Bachchan and Rashmika are seen sharing some light moments as the former fly a kite.
Directed by Vikas Bahl, Goodbye is a story about life, family, and relationships.
The film, which is produced by Ekta Kapoor, also stars Neena Gupta, Pavail Gulati, Elli Avram in distinct roles.
It is slated for Oct 7 release.