The house used as Barbara Stanwyck's character's home still stands today at 6301 Quebec Drive.
Edward G. Robinson's initial reluctance to sign on was largely because he had been demoted to third lead. Eventually, he realized that he was at a transitional phase of his career, and was getting paid the same as Barbara Stanwyck and Fred MacMurray for doing less work.
Author James M. Cain later admitted that if he had come up with some of the solutions to the plot that screenwriters Billy Wilder and Raymond Chandler did, he would have employed them in his original novel.
When Walter Neff first meets Phyllis Dietrichson, much attention is paid to her ankle bracelet ("anklet"). Urban legend states a married woman wears an anklet to indicate she is married but available to other men.
This film came out in 1944, the same year David O. Selznick released Since You Went Away (1944). Part of the campaign for the latter film were major ads that declared, "'Since You Went Away' are the four most important words in movies since 'Gone With the Wind'!" which Selznick had also produced. Billy Wilder hated the ads and decided to counter by personally buying his own trade paper ads which read, "'Double Indemnity' are the two most important words in movies since 'Broken Blossoms'!" referring to the 1919 D.W. Griffith classic. Selznick was not amused and even considered legal action against Wilder. Alfred Hitchcock (who had his own rocky relationship with Selznick) took out his own ads which read, "The two most important words in movies today are 'Billy Wilder'!"
Raymond Chandler: man sitting outside Barton Keyes' office reading a magazine who glances up at Walter Neff as he walks past, about 16 minutes into the movie.