Melissa McCarthy's husband, Ben Falcone, was attached to the project before she was. He recommended her for the lead when another actor backed out.

A pile of Lee Israel books ("Beyond the Magic", an unauthorized biography of Estée Lauder) are shown on sale at a bookstore for 75% off. Lauder was publishing her own memoirs and initially tried to pay Israel *not* to write her book, but she refused and rushed her book to publication. The autobiography was released in October 1985 and Israel's biography one month later. The book buying public chose to buy the Lauder autobiography rather than the Israel biography. Lee Israel later said she regretted not taking the money when it was first offered.

Although he portrays an alcoholic, Richard E. Grant is allergic to alcohol.

Julianne Moore was attached to this project during early development. She was fired from the project due to creative differences.

Filmed over a 28-day period in Manhattan, New York.

Richard E. Grant was recording an interview with Terry Gross for her National Public Radio program "Fresh Air" when Gross was the one who informed his that he had just been nominated for a SAG Award: "GROSS: I want to take a short break here and then talk with you some more. So if you're just joining us, my guest is Richard E. Grant. And he stars with Melissa McCarthy in the film Can You Ever Forgive Me? He won the New York Film Critics Circle Award for it, the San Diego Film Critics Society. Now he's nominated for a Golden Globe, an Independent Spirit Award and others as well. Oh, you just got nominated for a SAG. My producer just told me you're nominated for a SAG Award. GRANT: Wow. Wow. That's amazing. GROSS: Did you not know that? GRANT: No, how would I know that? GROSS: Oh, congratulations! GRANT: I've been talking to you. Sorry, I'm talking to you, so I had no idea. Goodness me. Thank you. GROSS: Oh, I'm sorry. I'm taking you away from the big news. Do you want to check your phone for a second and see? GRANT: I'm sure my daughter might have texted me. Can I just... GROSS: Sure. (Laughter) Take a break. GRANT: Let's have a look. Oh, wow, and Melissa has got one too. That's fantastic. Wow. God, I'm absolutely thrilled. Goodness me. There's nothing like the approbation of your own peers. GROSS: No, no. I know. I know. GRANT: Wow. You've got me at a emotional moment here. I never thought this would happen to me. Thank you. GROSS: Now that we've heard that good news, we're going to take the real break (laughter). And after we take a short break, I'll be back with Richard E. Grant. This is FRESH AIR."

According to Richard E. Grant, when the project was first in development, Sam Rockwell and Chris O'Dowd were originally cast in the role he plays.

Features the only Best Supporting Actor Oscar nominated performance of the year in a film not nominated for Best Picture.

The movie is full of nods to 'Withnail & I', which was Richard E Grant's first feature in 1987: Grant standing under an umbrella in the rain. Grant ordering 'Two double whiskeys'. Grant saying 'chin chin'. Clearing up a dirty kitchen and apartment that has rotting matter in it.

Melissa McCarthy's first portrayal of real-life person.

The film had its world premiere at the Telluride Film Festival on September 1. It also screened at the Toronto International Film Festival in September 2018.

"Crosby St. Books" is actually Housing Works Bookstore Cafe on Crosby St. Most of the used bookstore scenes (the ones with the green lampshades) were filmed at Argosy Books in Midtown East Manhattan.

In reality, Lee Israel and Jack Hock never reunited or communicated by phone after the FBI arrested him for acting as her accomplice. A few months before his death from an HIV-related cause (1994), she saw him in the waiting area of a Manhattan medical clinic for poor people. According to Lee's memoir that inspired the movie, she had the urge to trip Jack after he stood up from his seat, but she restrained herself. He did not see her.

At the premiere of the film, Richard E. Grant happened to meet Judy Sheindlin (Judge Judy) and asked her what she would have done had Lee Israel been standing in her court. Judy said that she would have given her a light fine because she did not kill anybody and, besides, the people dealing in celebrity memorabilia are possibly a little dodgy themselves.