When Cole and Linda spend the evening together she has her nails painted red, in the morning she has no nail polish on.
The order of the chorus girls auditioning for the solo in "Let's Fall in Love" changes between shots. The two women that Cole listens to switch places, before Alanis Morissette starts singing.
After the conclusion of "Let's Do It (Let's Fall In Love)" Linda reaches into her purse twice to give Cole his cigarette case.
In the finale scene where Cole is hugging the children, the order of the kids changes with the different angles (the girl skips between the right side and the centre).
When Cole Porter is in the garden playing his piano and Linda
comes back from being away, Cole stands and talks to her, and the cushion on the back of the chair falls down. As he sits down, the cushion is back in place.
The scene depicting the song "So In Love" on the opening night of "Kiss Me, Kate" depicts the song as a duet between the two leads during the show's Shakespearean play-within-a-play. In "Kiss Me, Kate," "So In Love" is not a duet. Both of the leads do sing solo versions of the song at a different point in the show, however neither takes place in the play-within-a-play.
The Porters attend a viewing of Night and Day (1946) at M-G-M Studios with L.B. Mayer. The film was produced by Warner Brothers.
When Cole Porter teaches Jack to sing "Night and Day", you can see where Jack's wig meets his real hair, at the back of his head, in several shots.
Late in the movie the Murphys arrive in a 1956 Cadillac to see Cole for the last time. Parked in front of his Massachusetts house is a 1966 Chrysler. Cole Porter died in 1964.
Scenes showing Cole Porter musicals being produced on Broadway in the 1930s show African-American and white women dancing together in the chorus lines. Broadway chorus lines weren't racially integrated until the 1970s.
The list of corrections would be extensive, but no attention is paid within the movie to place the songs in an accurate timeframe. An example would be the party where Cole met Linda (presumably in Paris in the early 1920s), during which Cole enlivens the proceedings with a rapid rendition of "Well, Did You Evah", which was composed in 1939 for DUBARRY WAS A LADY.
When Cole is riding the horse, there's the sound of galloping hoofbeats, but the horse is actually only moving at a canter.
In the song "Night and Day", Cole says, "Try E-flat" after the band has already started modulating to that key.
"De-lovely" accompanies the first portion of the end credits. The vocalist pronounces the word as "de-lux", though Porter specifically noted that the word should be pronounced "de-lukes".