After the novel's publication in 1974, the film rights went through years of studio rejections; between 1975 and 1981, at least sixteen major studios and distributors, including Columbia, MGM, United Artists, 20th Century-Fox, Paramount, and Warner Bros., all passed on making Fletch.

Producer Jonathan Burrows once tried disguising the script by giving it a different title and putting it in a different colored binder to get studios interested, but it still found no takers.

Author Gregory Mcdonald retained veto power over casting and rejected both Burt Reynolds and Mick Jagger for the role of Fletch; he agreed to Chevy Chase despite never having seen him perform.

Before Chevy Chase was cast, actors considered for Fletch included Jeff Bridges, Charles Grodin, Barry Bostwick, George Segal, and Richard Dreyfuss, the latter after Chase initially (and unknowingly, due to his manager) turned down the role.

Mcdonald sent Chevy Chase a telegram reading, "I am delighted to abdicate the role of Fletch to you," once Chase agreed to take the part.

Screenwriter Andrew Bergman wrote the first draft of the script in just four weeks, and the film later incorporated improvisation and a technique the crew called "dial-a-joke."

After reading the script, Mcdonald was angered by its deviations from his novel and wrote to the studio listing his objections; director Michael Ritchie invited him to the set and, over dinner, convinced him point by point that his concerns were unfounded.

Principal photography began in May 1984, with filming taking place in Salt Lake City International Airport, Provo, Orem, and Ogden, Utah.

According to co-star Tim Matheson, Fletch was Chevy Chase's first film role after recovering from drug addiction, and Universal specifically hired director Michael Ritchie to help keep Chase focused and comfortable on set.

Ritchie would often shoot one take following the script closely and a second take allowing Chase to ad-lib freely, giving rise to memorable improvised moments like Chase's character introducing himself as "Ted Nugent."

The film features numerous references to the Los Angeles Lakers, including cameo appearances by player Kareem Abdul-Jabbar and announcer Chick Hearn as themselves during one of Fletch's dream sequences.

The 2005 animated film Hoodwinked! directly parodies Fletch through its wisecracking wolf reporter character, right down to a Lakers shirt, disguises, and a version of Harold Faltermeyer's "Fletch Theme."

Fletch debuted in second place at the box office behind Rambo: First Blood Part II, eventually grossing $59.6 million worldwide and performing strongly on home video with $24.4 million in rental earnings.

Decades of attempts to revive the franchise followed, including a planned Kevin Smith-directed prequel with Jason Lee that was blocked by Miramax's Harvey Weinstein, and later development attempts involving Zach Braff and Jason Sudeikis, before Jon Hamm finally starred in the 2022 reboot Confess, Fletch.