The high school is named "Modine High School" after Matthew Modine who appeared in the previous film, Terror a 47 metros (2017).
Corinne Foxx and Brianne Tju lied at their auditions, claiming to the producers that they had stellar swimming skills when in reality, they had limited experience. Both were given lessons shortly before production.
Principal photography for the film took place in the Dominican Republic, Pinewood Indomina Studios, Dominican Republic, The Underwater Studio in Basildon and Pinewood Studios, UK, from December 2018 to February 2019.
The film had two previous titles, 48 Meters Down and 47 Meters Down: The Next Chapter.