He is portrayed by Robert John Burke.
Bart is introduced in The Wild Brunch when he throws the annual brunch for his foundation. At the brunch, it's revealed that he is dating Lily van der Woodsen and wants to make it public despite her hesitation. In The Handmaiden's Tale, Lily is invited to a party thrown by Eleanor Waldorf and decides to make Bart jealous by bringing her ex, Rufus Humphrey. They kiss in front of Bart, which prompts him to talk to her,In Victor Victrola, Chuck discovers Bart and Lily are dating, but also that Bart is still seeing other people. After his proposal to by a club is rejected by Bart, he tells her and she begins to ignore Bart. Chuck eventually tells him what he did, and Bart becomes angry with him; especially after he decided to invest in the club, Victrola, to teach Chuck about responsibility. During the Christmas season, Bart and Lily have gotten back together. In Roman Holiday, Lily tells Serena and Eric that she and Bart are dating. He proposes on Christmas morning and she doesn't answer right away. Later, after Serena asks her to marry Bart to keep her away from Rufus and her relationship with Dan, she accepts (School Lies). Soon after, the VDWs move into a hotel room with Bart and Chuck, but Bart finds trouble with the arrangement after Serena blames Chuck for a myriad of pranks pulled on her. He attempts to reform him by asking him to be his best man and offering to invest more in Victrola but after that fails, he asks Chuck to move out (The Blair Bitch Project). At the rehearsal dinner for the wedding, Bart becomes suspicious of Lily and her whereabouts with Rufus (Woman on the Verge). On the morning of the wedding he asks her to meet him at the site of the first building he ever bought and asks her to let Rufus go. She agrees and they marry later that day. Soon after, Bart learns that Chuck is planning to take Blair Waldorf to Europe for the summer. He advises him that he will learn about responsibility and compassion, and that he will return a changed man (Much 'I Do' About Nothing). The Serena Also Rises, Lily discovers that Bart has had her investigated and has several dossiers on her. He assures her that it's only for her protection then gifts her a necklace from his latest business trip. In Chuck In Real Life, Bart and Lily plan to throw a housewarming party in the hopes of impressing some clients of Bart. Eric asks if he can bring his boyfriend but Bart advises him not to, reasoning that he doesn't want to come out in a major news publication. Meanwhile, Serena is feeling like she's being controlled too much so she uses the party as an opportunity to sabotage the family image. However, Bart later chooses to kill the story after the party is a disaster. In There Might be Blood, Dan is asked to write an exposé article on Bart for a major magazine. He masks his interview by pretending to be genuinely interested in what Bart does, and Bart agrees to let him shadow at the office a few days a week. Meanwhile, Chuck tries to get closer to his father but Bart isn't interested. He attempts to give Bart hockey season tickets but Bart uses them to take Dan and hang out. Jealous, Chuck quickly figures out what Dan is up to but doesn't say anything until Dan begins questioning Bart about insurance fraud committed in one of his buildings. As an apology Dan sends Bart an excerpt from the story he's writing where he shares how Chuck feels Bart hates him for killing his mother. After reading it, Bart explains to Chuck that he never once blamed him for his mother's death and that being close with him is hard because he reminds him of her so much. He then asks Chuck to attend a hockey game with him. At Thanksgiving, Chuck shows Eric the files that Bart keeps on him, Serena, and Lily. Eric then tells Lily, who becomes angry at the tabs Bart is keeping on the kids. She orders him to stop and leaves before dinner (The Magnificent Archibalds). In It's a Wonderful Lie, Bart asks Lily to give him a chance to change. However, Lily is preparing to leave him to be with Rufus. She agrees to let him escort her to the Snowflake Ball at Constance/St. Jude's but later changes her mind and decides to go without him. At the ball, Chuck sees Lily with Rufus and calls Bart to inform him. Meanwhile, Bart is on his way back from Florida and in a car with his PI, Andrew Tyler, who has information on Lily. Before Bart can get to the dance the car crashes, killing him.
In O Brother, Where Bart Thou? Lily listens to the last message Bart left for before he died. In it he claims to know why she was in a hospital in France. In Gone with the Will, Bart's lawyer gives Chuck a letter Bart wrote to him before he died; in which he bequeaths Chuck the majority share of Bass Industries.The Debarted Bart reappears as a ghost to Chuck on the anniversary of his death. He tells him that he is weak for not putting his business first and for opening up to Blair and letting her in. Worried about Chuck, Blair goes to Lily to ask her to talk to Chuck about going to the burial site. He refuses at first but agrees to go with Blair after visiting a hospitalized Serena and seeing visions of the night Bart died.
In The Kids Are Not Alright, an old enemy of Bart's, Russell Thorpe, returns to town. When he finds out Bass Industries is for sale, he vows to buy it and dismantle it as revenge for Bart mistreating him. In Empire of the Son Russell reveals to Chuck that he hates Bart because when he burned his old building down to collect the insurance money his wife, Avery, was inside and died. Chuck has his PI look into it, and Andrew finds a tape from the night of; as well a a letter from Avery apologizing for leaving someone. In Shattered Bass, Chuck realizes that Avery was planning to leave Russell for Bart and instead of Bart being responsible for her death, Russell is the one who trapped her.Raiders of the Lost Art Blair, Chuck, Nate, Serena, and Lola travel to a mansion outside the city to find the truth behind Diana Payne. While there, Blair enters a room and finds Bart inside. When she leaves, she tells Chuck what she saw and he heads back in to investigate. The next morning, Bart explains to him that he had to fake his death to avoid having the entire family murdered by one of his competitors. After the car crash he paid off one of the doctors to turn off the machines and pronounce him deceased. Wanting to bring his father out of hiding, Chuck tracks down the man who wanted him dead and plans to set him up. However, he finds out that Andrew Tyler was also involved. He has both men arrested and Bart is then able to emerge from hiding (The Fugitives). In The Return of the Ring Bart meets with Lily to discuss their marriage, since she is technically married to both him and Rufus. Bart expresses interest in rekindling things, but Lily initially brushes him off. Meanwhile, Rufus learns that one of Lily's marriages has to be annulled, and serves Bart divorce papers on her behalf. Bart signs them, but Lily is surprised when she sees the papers. At the same time, Chuck is preparing to welcome Bart back to Bass Industries and is excited to be working with his father. However, Bart chooses to cut Chuck completely out of the company and take the reigns back himself. Afterwards, Lily decides to annul her marriage to Rufus in order to fix things with Bart. Gone Maybe Gone Chuck brings Amira, a woman Bart met in Dubai, back to Manhattan to figure out a way to take him down. When Bart learns Amira is in town, he offers her ten million dollars to keep her quiet on their affair and a secret of his. She takes the money but agrees to work with Chuck to find out what he's really hiding. Soon after, both Lily and Chuck discover that Bart and Amira had an affair and Chuck becomes angry that she didn't disclose that earlier. He orders her to write down anything and everything from the weekends they spent together. However, Bart is able to get her out of the country before she can. Later, she sends Chuck a surveillance photo of herself and Bart going to meet with a man in Dubai and says that's the only person they saw that weekend (High Infidelity). After some investigating Chuck finds out that the man in the photo was Bart's bodyguard and he was taking him to meet with someone named Lady Alexander (Dirty Rotten Scandals).
In Portrait of a Lady Alexander Chuck and Blair learn that Lady Alexander is a horse that Bart bought for just under a million dollars; as well as several other thoroughbreds in one month. They learn that she was sold to someone named Sheikh Hassan, whose daughter they track down at a horse show. Meanwhile, Bart offers to back Nate's failing newspaper, The Spectator, if Nate writes good press on Lily. Nate refuses the offer and Bart reminds him how his father was inventive with numbers. After meeting with Iman, the Sheikh's daughter, Chuck realizes that Bart's horse sales were a coverup for his illegally trading oil with Sudan; a crime that is a violation of US federal law and punishable by prison time. At the same time, Bart secretly backs Nate's paper when he finds out Nate lied about how well the paper was doing when looking for investors. Soon after, Bart reveals what he did to Lily but promises that no one got hurt (Monstrous Ball).
In Where the Vile Things Are, Lily, in an attempt to ruin Rufus and Ivy's art gala, sells a painting in which Bart hid the records of his oil trades. Meanwhile, Chuck has figured out where they are and ends up in a bidding war with Lily and Ivy, but they all ultimately lose to Rufus. Chuck offers to buy it from Ivy but is angry upon realizing Ivy took the records before sending him the painting. In Save the Last Chance Ivy reveals to Bart and Chuck that she has the records and will give them to whoever hurts Lily the most. Bart says he is going to divorce Lily and Chuck plans to pretend to have her arrested as an accomplice to Bart's crimes. However, Bart is able to blackmail Nate into revealing Chuck's plan to Ivy. Not satisfied with his plan to just divorce her, Ivy suggests they also take pictures to make it look like they slept together to humiliate her more. Bart is willing to do so until Ivy is unable to provide the records; as Rufus swiped them before she left the loft and gave them to Lily. Dan is able to alert Chuck about where the records are but he fails at stopping Lily from burning them to protect Bart. In It's Really Complicated it's revealed that both Sheikh Hassan and Bruce Caplan, the Bass business manager, both died in mysterious accidents via Bass provided transportation. Blair suggests that if they can find a way to tie the two deaths together and present it to Lily they can get her on their side. They successfully drop enough hints and Lily leaves town for a few days to escape Bart, whom she no longer feels safe around. On her way out, she calls Chuck to tell him that she is fearful for their lives and promises to send him anything she can remember from the records.
Soon after, Bart is about to be honored as Man of the Year at a party in The Revengers. Blair suggests to Chuck that they can bluff a confession from Bart. They attempt to do so but accidentally get Nate arrested instead. Afterwards, Bart tells Chuck that the only way to ensure Lily, Blair, and everyone else's safety as well as getting Nate out of jail is for him to leave for Moscow, Russia, that night and never come back. Chuck refuses the offer at first, but changes his mind after Bart briefly kidnaps Blair. At the party, Blair, Serena, Ivy, Georgina Sparks, and Sage Spence taunt Bart with small reminds of his crimes. While Bart confronts Blair about it, they see a story on the news about how a Bass jet has gone MIA and Bart alludes that Chuck may have been on the flight. However, Chuck enters the party at that moment and accuses Bart of trying to kill him. Bart has him removed from the party and brought to the roof. He meets him up there and the two begin an argument that turns physical. Bart attempts to lunge at Chuck but accidentally launches himself onto the edge of the building, Blair arrives just in time to witness Bart fall to his death.
In New York, I Love You XOXO Chuck and Blair are questioned about Bart's death, but it is eventually ruled an accident.
- Misty Bass (wife)
- Chuck Bass (son)
"But to be honest, I haven't seen anything in the last year that suggests you have what it takes. If anything, you've been a disappointment. You opened your heart to Blair and it made you weak. You cannot be one person at work and another one at home. If you're soft, you're soft. And let's face it. You're soft." -The Debarted (3x12)
"Maybe hiding all these years was easier than facing things head on." -The Fugitives (5x23)
"No one does a big romantic gesture better than a Bass." -The Return of the Ring (5x24)
"Blair has nothing to do with the way I've handled this business!" -Chuck
"You didn't try and trade her for a hotel deed? You didn't let everything fall apart when you ran away from her all the way to Europe? You didn't just three months ago nearly bankrupt yourself trying to get her out of her marriage? I had hoped you would have outgrown such foolish behavior but you're still willing to throw everything away for a girl whose done nothing but toy with you." -The Return of the Ring (5x24)
"I can buy whatever I want. It's one of the perks of being really rich." -Gone Maybe Gone (6x1)
- He turned his first profit when he was 22.
- He used to sneak into hockey games as a kid.
- He was born into a poor family.
- He was close friends with Sheikh Hassan and his daughter Iman calls him "Uncle Bart."
- He eats veal on a regular basis and killed a tiger on safari once.
- After CeCe Rhodes, Bart is the second recurring character to die.