Adura Onashile began developing Girl in 2017 with Rosie Crerar and Ciara Barry of the production company barry crerar. barry crerar also produced Onashile's short film Expensive Shit (2020). Girl was developed with iFeatures and BBC Film,[5] and received support from the British Film Institute (BFI) and Screen Scotland.[6]
The production team decided to search internationally when casting the lead character Grace and happened upon French actress Déborah Lukumuena.[7] Le'Shantey Bonsu was scouted for the role of Ama through her primary school's drama programme in Leeds. Onashile incorporated elements from Lukumuena and Bonsu's backgrounds into the film.[8] Also starring in the film are Danny Sapani and Liana Turner.
Principal photography took place in Glasgow over the course of six weeks and wrapped in October 2021.[6]