Florence Foster Jenkins created all her own outfits, inspired by the style of "a Mexican señorita" and 18th-century ball gowns. She also designed her pair of heavenly wings. According to costume designer Consolata Boyle, "She was a supreme performer, so her clothes were gorgeously outrageous. They were high camp but with a softness so she drew people in. And she had no embarrassment about how she looked."
Hugh Grant had semi-retired when director Stephen Frears convinced him to star in this film. Grant said he participated in the film to act opposite Meryl Streep.
Florence Foster Jenkins was in an accident while in a taxi. She was unharmed, but gave the taxi driver a box of cigars because she could now hit a higher note than she could before the accident.
Meryl Streep and Simon Helberg recorded all of their songs together at Abbey Road prior to filming. Once filming began, director Stephen Frears asked them to perform all of the music live, on set.