Palumbo made his debut appearance on World Championship Wrestling (WCW)'s Nitro on October 19, 1998 as a fan who accepted the challenge of Ernest "The Cat" Miller.
In 2000, Palumbo made his debut on the March 22, 2000 edition of Thunder, losing to Scott Steiner. After this match, Palumbo was chosen by Eric Bischoff and Vince Russo to be the New Blood's version of Lex Luger in May 2000. He was given the nickname "The Main Event".
Palumbo feuded with Luger until late May 2000 when Palumbo formed a team called "The Perfect Event" with Shawn Stasiak and the pair won the WCW World Tag Team Championship. Their main feud was against KroniK (Brian Adams and Bryan Clark). In August, Stasiak and Palumbo helped form The Natural Born Thrillers with Mike Sanders, Sean O'Haire, Mark Jindrak, and Reno. They were briefly "coached" by Kevin Nash.
Palumbo and Stasiak won the WCW Tag Team Championship two more times before splitting in early January 2001 when he and Stasiak won a tag team battle royal with O'Haire and Jindrak for a future tag team title shot. After the conclusion of the match, Mike Sanders declared both teams victorious and that any combination of the four would face The Insiders (Diamond Dallas Page and Kevin Nash). Palumbo and O'Haire were the two members of the Natural Born Thrillers who would face and defeat Page and Nash for the tag titles at Sin on January 14, 2001. Following the title victory, the Natural Born Thrillers broke up when the team of Jindrak and Stasiak became jealous of Palumbo and O'Haire. The teams faced each other at SuperBrawl Revenge on February 18, 2001 for the tag team titles, which Palumbo and O'Haire retained. The duo also retained the title against Totally Buffed (Buff Bagwell and Lex Luger) at Greed in March, WCW's last pay-per-view. On the final episode of Nitro, Palumbo and O'Haire defeated Team Canada's Mike Awesome and Lance Storm in the final WCW World Tag Team Championship title defense on the program.
Palumbo and O'Haire made their WWF debuts on the June 28, 2001, episode of SmackDown! as part of The Alliance, attacking the Hardy Boyz. O'Haire and Palumbo started feuding with the Acolytes Protection Agency (A.P.A.) in the following weeks, which ended at WWF Invasion on July 22, 2001 when the Acolytes Protection Agency defeated them. Subsequently, O'Haire and Palumbo defeated the Hardy Boyz on the August 2, 2001 edition of SmackDown!. O'Haire and Palumbo next dropped the WCW Tag Team Titles to The Brothers of Destruction (The Undertaker and Kane) on the August 9, 2001 edition of SmackDown! and lost their rematch for the tag team gold in a steel cage match the following week on Raw. O'Haire and Palumbo's last televised match together was on the August 26 edition of Heat, defeating The Holly Cousins (Hardcore and Crash).
Palumbo was thrown out of The Alliance on the October 25 edition of SmackDown by storyline co-owner of The Alliance, Stephanie McMahon. He joined the WWF in November.
When he returned, Palumbo found a tag team partner in Billy Gunn. The pair started as a tag team working dark matches, but were later given a gimmick that saw the pair grow increasingly affectionate towards each other, showing evidence of a relationship. Palumbo became known simply as Chuck, and he bleached his hair blond to match Gunn's.
On the February 21, 2002 edition of SmackDown!, Billy and Chuck defeated Tazz and Spike Dudley to win the World Tag Team Championship. Palumbo made his WrestleMania debut at WrestleMania X8, when Billy and Chuck defend their titles in a four corners elimination match against the APA, The Dudley Boyz, and The Hardy Boyz. They lost the tag team gold to Rikishi and their stylist Rico Constantino, who was forced to team with Rikishi on May 19, 2002 at Judgment Day. Less than a month later, Rico helped Billy and Chuck recapture the title, but they later lost it to Edge and Hulk Hogan.
In the second half of 2002, Billy and Chuck were the source of controversy when Chuck apparently proposed to Billy on September 5, 2002 edition of SmackDown! asking him to be his "partner for life". They had a marriage ceremony on the 2002 season premiere of SmackDown!. Just before they tied the knot, however, they revealed that the entire ordeal was a publicity stunt, and both characters disavowed their on-screen relationship. When Billy and Chuck decided not to go through with the marriage, Rico turned on them by helping Eric Bischoff and 3-Minute Warning attack the duo. Rico subsequently jumped to Raw as the manager of 3-Minute Warning, who beat Billy and Chuck at Unforgiven. Billy was injured in early October 2002, and Chuck worked on Velocity for a few months using his original ring name Chuck Palumbo once again.
In February 2003, Palumbo formed The Full Blooded Italians (F.B.I.) in WWE. After a beating at the hands of Rikishi, Nunzio threatened to bring in his "family" in order to gain revenge. The next week, Chuck Palumbo and Johnny "The Bull" Stamboli joined Nunzio to form the F.B.I. and attacked Rikishi. This version initially gained little success, but would go on to have brief feuds with Los Guerreros, Chris Benoit, Rhyno, Brian Kendrick, Nathan Jones, the APA, and The Undertaker.
Palumbo was traded to the Raw brand on March 22, 2004 along with A-Train in exchange for Rico and Jackie Gayda. After Palumbo was traded to the Raw brand, he was kept off television until July 2004, when he debuted with a new look and entrance music. His new image resembled a cross between an auto mechanic and a greaser. He would later give himself the nickname "Custom Chucky P." It was not long before Palumbo was a regular on Sunday Night Heat. His new gimmick started off usually losing matches but began to rise on Heat, defeating the likes of The Hurricane, Rosey, Val Venis and Stevie Richards. On the October 31, 2004 airing of Heat, Palumbo had his most high-profile match on the Raw brand when he faced former World Heavyweight Champion Chris Benoit, but was defeated. Palumbo was released by WWE soon after on November 4, 2004.
In March 2006, Palumbo re-signed with the WWE and began working house shows and dark matches over the next year. Palumbo officially returned on the May 25, 2007 edition of Heat with a biker gimmick, and defeated Charlie Haas. He then continued making appearances on Heat, where he consistently defeated jobbers. On July 6, 2007, Palumbo made his SmackDown! re-debut, defeating Kenny Dykstra in his return match.
Palumbo began an on-screen relationship with Michelle McCool, whom he teamed with to defeat Dykstra and Victoria in a mixed tag team match. He then feuded with Jamie Noble, after Noble made advances towards McCool. After a series of matches between the men, Noble won a date with McCool by defeating Palumbo. Palumbo accidentally elbowed McCool during a match, causing her to suffer a storyline concussion. The partnership was dissolved when McCool refused to accept his apology the following week. Palumbo vowed to get revenge on Noble, and defeated Noble the following week.
Palumbo participated in the Royal Rumble match, where he eliminated Jamie Noble. He next appeared at WrestleMania XXIV, taking part in a 24-man inter-promotional battle royal to crown a number one contender to the ECW Championship, where he also eliminated Noble. During a series of house shows in June 2008, Palumbo challenged Matt Hardy for the United States Championship, though he was unsuccessful in winning the championship. As part of the 2008 WWE Supplemental Draft, Palumbo was drafted to the Raw brand. He never made his return to the brand however, as he was released from his WWE contract on November 7, 2008.