At one stage the script was considered being filmed as a television pilot, but in the end the studio decided to go ahead and make it as a feature film. The reverse would later happen with Home Alone 4 (2002), which was originally intended to be a stand-alone TV movie, but was restructured during production to serve as a pilot for a TV series that ultimately never went ahead.
A rare positive review came from Chicago film critic Roger Ebert, whom on his TV show Siskel & Ebert (1986) called the film better than the first one, Gene Siskel nearly fell off his chair in disbelief at this remark.
The original concept involved Macaulay Culkin's character, Kevin McCallister, returning as a teenager. However, the plan was scrapped as Culkin dropped out of acting three years earlier as he thought he was outgrowing "childish" roles.
The role of Alex was a coveted one, with over 100 kids trying out for the part. Alex D. Linz won the part, beating another child star, Philip Petrie, who had also tried out for the part of Sammy in One Fine Day (1996), a role taken by Alex D. Linz.
The film is completely independent of the original movies. There no mention of Kevin or the McCallisters. The only link to the original Home Alone (1990) or Home Alone 2: Lost in New York (1992) is the Chicago suburbs, where the original film takes place, Mr. Jernigan getting his region hit by a crowbar and a portion of John Williams' score during the beginning credits. Marv and Harry were not mentioned either.
John Hughes approached Chris Columbus to direct the third installment once again, but Columbus declined suggesting it should be directed by a filmmaker making his directorial debut as the original Home Alone (1990) was the first film where he received public recognition as a director. Columbus also didn't feel comfortable working with an entirely new cast. Hughes then approached Raja Gosnell who at the point was noteworthy for editing the first two films and he was given the job.
Originally the screenplay was written with the villains being former partners in crime to Marv and Harry from the first two films, but when Macaulay Culkin and the rest of the first two films cast declined to have any involvement with this sequel John Hughes refused to make any reference or connection to the previous installments.
While this is the second Home Alone movie to feature a bad guy with a gun (or in this case, several all the bad guys), this is the only one in the franchise in which gun shots are fired from the villains.
When Macaulay Culkin declined to reprise his role as Kevin for the third outing, John Hughes briefly considered writing the screenplay with Joe Pesci and Daniel Stern reprising their roles as burglars Harry and Marv, respectively who target Kevin's cousin Fuller (Macaulay's real life brother Kieran Culkin), and Fuller would be the main character with Gerry Bamman and Terrie Snell reprising their roles and Fuller's parents Frank and Leslie respectively, who go on vacation and leave Fuller home alone, to defend himself against Marv and Harry. The idea was scrapped as Pesci and Stern refused to reprise their roles and wanted to pursue other projects, and Kieran felt he couldn't follow in his brother's footsteps as the lead. Hughes then re-wrote an entirely different screenplay with no characters from the first two films.
Originally, the concept of this film was to have Macaulay Culkin reprise his role as Kevin McCallister. This time instead of having Marv and Harry return as the burglars, Kevin would be defending himself against a group of new villains.
Alex shovels snow for the grouchy Mrs. Hess whom he fears but later gets to know. In the original Home Alone, Old Man Marley shovels snow and is feared by Kevin because it is rumored that he is a serial killer.
The trivia items below may give away important plot points.
The scene in the garage where Jernigan sees a pair of legs dangling out of the storage attic and he pulls on them which are actually the legs of a dummy attached to a lawn mower starter which starts and falls through the door onto Jernigan was derived from the novelization of Home Alone 2: Lost in New York (1992) in which the exact same incident happens to Marv when he's searching the garage for Kevin.
This is the only film in the theatrical franchise where any of the relatives (in this case, the mom and the older siblings) find out that the main character(s) may be in danger and took down the bad guys by himself.