Nick Offerman (Joe's father) and Megan Mullally (Patrick's mother) are actually real life husband and wife.

Director Jordan Vogt-Roberts brought in cast member and improviser Craig Cackowski prior to shooting in order to teach the young cast basic improv techniques. Vogt-Roberts wanted the actors "living in the skin of the characters" between takes. The director would then secretly film the actors between takes, in order to capture a more natural, authentic camaraderie. He had a code word for his crew to secretly start rolling. According to actor Marc Evan Jackson, much of this vérité footage made the final cut.

Chris Galletta's script was featured on The Black List (an annual comprehensive list of Hollywood's best unproduced scripts) in 2009. Other notable scripts featured on the list that year include The Social Network (2010), Cedar Rapids (2011), and Take This Waltz (2011).

The screenplay was originally titled Toy's House.

At one point, Biaggio (Moises Arias) says he thinks he's gay because his "lungs fill up every time the seasons change," after which Joe (Nick Robinson) says, "That's not being gay ... pretty sure that's cystic fibrosis." In "Five Feet Apart," Arias plays Poe, gay character who has cystic fibrosis.

Megan Mullaly and Allison Brie appear in The Diaaster Artist (2017).

Nick Offerman, Megan Mullaly and Marc Evan Jackson have previously appeared in Parks and Recreation.

Nick Offerman, Marc Evan Jackson and Mary Lynn Rajskub are guest stars in Brooklyn Nine Nine.

The snake shown at the end of the film is a Pacific Gopher snake which is not venomous as portrayed in the film.

At the end of the movie, in the hospital, Joe is wearing a Cleveland t-shirt; giving a hint to the movie's filming location.