Five identical Pontiac GTOs were built (two were totally destroyed) for the movie. This muscle car was chosen the film to distance itself from the earlier Artisan version of The Punisher (in which action star Dolph Lundgren rode a motorcycle throughout).
With the supervision of a trainer, Thomas Jane worked out extensively for the role with two hours of weight lifting and cardio, sometimes twice a day and a rigorous diet of health shakes. Jane also trained with multiple firearms and weaponry.
The words that Frank Castle writes near the end of the film, listing the bases of his vigilante philosophy in numbered order, form the beginning of his war journal, an ongoing diary of his campaign against organized crime. It was the basis for the long-running comic book "The Punisher War Journal".
Rebecca Romijn revealed that in a scene where she sews up a knife wound on Thomas Jane, she pushes the needle too far in and ends up actually sewing a couple of stitches on Thomas Jane's body instead of just the prosthetic wound.
The Castle family house in Puerto Rico are really restrooms/changing rooms located in Honeymoon Island State Park, Dunedin, Florida. State Parks adhere to strict rules about color of their buildings, the restrooms/changing room where re-painted from their original grey to the colors seen in the movie, they remain that color since the movie was released.
Jonathan Hensleigh actually knew someone who parked illegally for two years in Manhattan by using the same bogus fire hydrant ploy Frank Castle uses to keep Livia's parking space open during his schemes.
In a subplot of the film, which was cut, Frank Castle finds out that Howard Saint got his information from his friend FBI Agent Jimmy Weeks. He eventually stalks him and drives Weeks to commit suicide. This was included in the extended DVD cut.
When the teaser trailer was shown, there was negative reaction to the solid white skull logo which has been the character's trademark in the books. The costume designer changed it to a "worn-down" design that better suited Frank Castle's character in the film.
When Castle is readying himself to administer the coup de grace to Saint, he attaches a shoulder stock to a pistol. This is presumably supposed to be a Glock 18, a version of the Glock 17 9mm capable of fully automatic fire. This is uncertain, however, since the piece never appears again in the film.
The weapon Castle uses in the final shootout is a Colt M4A1 carbine, a shortened version of the M16 rifle. Castle's is modified with a flat-top upper receiver with a Picatinny-type accessory rail, an M203 40mm grenade launcher , and an Aimpoint M68 Close Combat Optic.
Scenes were constantly scaled back or cut to meet budget requirements. Effects scenes were almost always done the old-fashioned way with old tricks replacing new CGI. Jonathan Hensleigh discusses this in the commentary track of the original DVD edition
Many of the characters, including Joan, Bumpo, Spacker Dave and The Russian, all come from the punisher series "Welcome Back, Frank", written by Garth Ennis and illustrated by Steve Dillon and Jimmy Palmiotti. Timothy Bradstreet illustrated the covers, along with the promotional posters for the movie.
Frank's tenement building was located at the corner of N. Nebraska Ave. and E. Zack St., directly across the street from the Tampa Amtrak station. It was a fairly well known local landmark due to it's unusual shape, but has since been demolished.
Was originally slated to be a sequel with Thomas Jane returning as Frank Castle/The Punisher with Jonathan Hensleigh returning to direct it as well. The writing development had went on for three years but by 2007, both Jane and Hensleigh left due to creative differences and also the budget being cut. After they left, Lionsgate then decided bring in director Lexi Alexander and actor Ray Stevenson to play The Punisher and rebooted the film into what is now Punisher: War Zone.
When shooting the surprise retirement party for Frank Castle (Thomas Jane) after the success of the major sting, the group of extras behind the table were directed to make simple cheers once Thomas Jane walked in. This scene was shot several times because a certain actor kept fumbling his lines. On one such entrance of Thomas Jane, he commended the extras and told them that he actually felt like they were real and sincere with their praise for him.
Thomas Jane initially turned down the role twice, as well as a part in X-Men, as he didn't see himself as a superhero actor. He only became interested in the character after being asked to play him for the second time and he had seen Timothy Bradstreet's artwork of the character.
Jonathan Hensleigh was dismayed before filming began when he learned that he wasn't going to be given sufficient budget for a top flight action movie. He felt he needed in the region of $64 million but was only given $15 million instead, and only 52 days to shoot the picture. Hensleigh had to rewrite a lot of his original script to accommodate this reduction in budget and shooting schedule.
The scene when Howard Saint visits Quentin Glass in his home at night was actually shot in the middle of the afternoon. The evening effect was achieved by tenting up the real-life house that was being used as Glass's home.
John Travolta allowed Thomas Jane to have his name first in the credits and advertising so that he could work on this project. In fact, he didn't mind it at all, allowing Jane to be put over so he can get recognition as the main character.
The scene in which hot oil is tossed on to The Russian was scaled back due to excessive violence. Originally, blood was supposed to pour from The Russian's eyes, but it was deemed "too much" by the MPAA.
The Saints and Sinners Club shootout between Frank Castle and Howard Saint's goons was originally longer, but was cut because of pacing and explicit bloodshed. The only two scenes that were altered because of violence were: 1: The point-blank head shot featured blood squirting from the back of a thug's head. 2: The scene in which a thug is dispatched by way of sawed-off shotgun was also cut. The original scene feature pieces of the thug being sprayed from his wounds.