A hostage was someone who was held by a captor in order to compel another party to act, or refrain from acting, in a particular way, often under threat of serious physical harm to the hostage(s).
- Kim Bauer and Teri Bauer: Along with her friend Janet, Kim was kidnapped by Dan Mounts and Rick Allen and handed over to mercenary Ira Gaines. Teri was kidnapped by Kevin Carroll, who was posing as Janet's father Alan York. Gaines kept Kim at his compound with her mother for several hours, threatening to kill them if Jack didn't comply with his demands. Kim and her mother were eventually rescued by her father with help from CTU and Alberta Green.
- Janet York: While unaware at the time, Janet was kidnapped with Kim by Dan and Rick. Their boss, Ira Gaines, wanted the boys to hand him Kim and Janet and then he would kill Janet. Janet's arm was broken by Dan and she and Kim tried to escape. In their attempt, Janet was hit by a car and left for dead, but an ambulance arrived on the scene and took her to St. Mark's Hospital.
- Jessie Hampton: Officer Hampton was held by Greg Penticoff in order to draw Jack away at 18166 San Fernando Road. Instead of letting Jessie go, he shot her and was captured by Jack. She was killed instantly.
- Nina Myers: When Nina became suspicious of Jack's actions at CTU and the switching of the keycard, he held her at gunpoint and exited CTU with her. Gaines ordered Bauer to shoot her, which he did, but prevented her death with a flak jacket.
- Lauren Proctor: After escaping from Secret Service custody, Jack carjacked Lauren and held her hostage until he received a car with help from Nina Myers and Tony Almeida. She agreed to retrieve the car for Jack, but betrayed him and alerted Secret Service.
- Ted Cofell: Jack knocked out Cofell's driver Mark and kidnapped Cofell in his own limousine, later interrogated him and threatened to force a towel down his throat. Cofell pleeded innocence until they went to see Kevin Carroll, when he attacked Bauer with a Microtech HALO; Jack inadvertently killed him by rupturing his heart condition with a punch.
- Kevin Carroll: When he went to meet Cofell, Kevin was trapped in the limo by Jack, who knocked him out by swerving the limousine. He was tied up with tape and made a deal with Jack to lead him to the compound where Teri and Kim were being held if Jack released him.
- Krugman: During the botched drug deal, Frank Allard and his friend Craig held undercover officer Krugman and his partner at gunpoint and stole the drugs. Krugman arrested them later and was shot by Serbian terrorists.
- Victor Drazen: When Andre Drazen's team of Serbian militants entered the Class 3 Detention facility, Jack held Drazen hostage when surrounded. He released him when Andre threatened to execute the warden.
- Mark DeSalvo: Held by Andre Drazen as leverage to release his father. Jack released Victor but Andre shot Mark anyway in front of Bauer.
- Jack Bauer: Taken by the Drazens as a bargaining chip after the death of the entire staff at the prison in Saugus. Exchanged for Alexis Drazen.
- Kim Bauer: After being released from prison with help from Melanie, the police car escorting Kim to CTU was attacked and the cops, including Krugman, were shot and Kim was taken again. She escaped and was found Sargeant Devlin at the Port of L.A.
- Mila Luminović: After serving her father and Victor, Jack held her with a knife to her neck and ordered the Serb's guns to be lowered. Victor agreed to, but shot Mila in the forehead, destroying Jack's leverage.
- Kate Warner and Paul Koplin: Captured by Syed Ali, Paul and Kate were torured by a terrorist Mohsen. Mohsen killed Paul and was ordered to murder Kate when Jack and the CTU team rescued her and took Mohsen hostage. He later committed suicide by using a suicide capsule.
- Asad Ali, Fareed Ali, and their mother: Held by their government in a deal with CTU as leverage over Syed Ali. CTU and Jack faked the death of Asad but Syed wouldn't talk, and then threatened the life of Fareed.
- Ryan Chappelle and Michelle Dessler: Captured by Peter Madsen and Sid Wilson's men at CTU headquarters. Chappelle was immediately captured while Dessler was in hiding and gave herself up in order to help Kim Bauer escape into the other data rooms.
- Kim Bauer: Captured by Peter Madsen's men so that Jack would bypass a few key security protocols and help them with a few illegal actions.
- Kate Warner: Captured by Peter Madsen as leverage and later in order to draw Jack Bauer out once they realized Bauer had survived the initial attacks despite Chase Edmunds (who was still undercover at the time) claiming otherwise.
- Kyle Singer and Linda: After escaping the mall, Kyle met up with Linda but both were soon captured by Mexican terrorists. They were held in some kind of incubation chamber and later escaped.
- Ramon Salazar: When Jack Bauer broke Ramon out of prison, he held Ramon as his hostage to get away from CTU until they boarded a plane along with Tomas, Pedro and Sandra.
- Ramon Salazar and Jack Bauer and prison guards: After the riot, Peel and other prisoners forced their hostages to play Russian roulette. Buchanan and another guard were killed and Peel died when Jack shot him.
- Kim Bauer: Tied up by Gael Ortega in CTU when she dscovered he was a mole working for the Salazars. A lockdown was ordered by Michelle Dessler and Gael was caught but pardoned by Tony Almeida because he was part of an elaborate sting operation involving Kyle Singer.
- Chase Edmunds: In Mexico, Chase was captured by Hector Salazar's men and tortured by Eduardo later at the Salazar estate. He escaped with the help of Claudia Hernandez and was later captured for a short time by Nina Myers.
- Michelle Dessler: After the Chandler Plaza Hotel incident, Michelle was captured by Frederick, one of Saunder's henchmen, who, under orders from Saunders, threatened to mutilate and kill her if Tony didn't follow commands.
- Jane Saunders: Captured after a sting operation incliding Kim Bauer and Alice, Jane was used as leverage against Saunders and eventually he surrendered his vials and gave up the names of his couriers.
- Nina Myers: In Mexico, Nina was held hostage by Jack after he killed her guards but she quickly turned the odds in her favor by knocking him out and taking him hostage. She kissed him and escaped later and took Chase Edmunds hostage but was punched and re-captured by Jack. On the plane back to Los Angeles, she tricked Jack into releasing a computer virus in the computer systems in CTU. Her virus was eventually deleted by Chloe O'Brian, and Nina was killed by Jack to get his revenge for Teri's death.
- James Heller and Audrey Raines: Captured by terrorists and were to be executed on live television for "war crimes". Eventually rescued by Jack Bauer.
- Officer Bill Dotson, Kalil Hasan, Doug, Brett, and a woman: Police officer, a terrorist, and civilians held at Doug's store by Jack in order to buy time for satellite coverage. The civilian hostages were not harmed by Jack.
- John Hansen: Held by an assassin, Nicole, who handed him off to Mitch Anderson who used him to get onto a stealth fighter. Hansen's family was also held hostage and Mitch killed John at the airfield.
- Behrooz Araz: Captured by his father as a hostage then by Jack then held first by CTU then exchanged to the terrorists for Jack. His whereabouts are currently unknown.
- Tony Almeida: Held hostage by Mandy, to force his wife, Michelle Dessler to find a way to help her escape from the CTU agents. Tony was successfully rescued, and returned to CTU.
- Jack Bauer: Held by terrorists Polakov and Komar at the mall. Escaped and later captured by his old boss at Omicron International. Later, Henderson trapped Bauer in the Sentox development bunker and planned to kill him with a bomb.
- Miriam Henderson: Held as a hostage by Jack in her home and claimed not to know anything about her husband's illegal activities. She was later shot during Christopher's interrogation and received medical attention.
- Curtis Manning: At Collette Stenger's apartment, a German agent held Curtis hostage and released him when Jack arrived.
- Collette Stenger: After being caught by Jack Bauer, Collette named Audrey Raines as her source of stolen schematics. After Jack deemed Audrey as innicent, he entered Collette's cell, knocked out her guard and threatened to kill her unless she told the truth. She eventually broke and Audrey was released.
- Audrey Raines: At the Van Nuys airport after meeting her father, Audrey was taken by Henderson and was traded for the recording. He punctured her brachial artery and she started to bleed. She survived and was kept at CTU later.
- Christopher Henderson: After he injured Audrey, Henderson escaped and handed off the recording to Scott Evans. Jack and Audrey caught him later and he was held by Audrey after Jack went after the recording. His team rescued him but Audrey was safetly taken by Curtis.
- Flight 520: Jack hijacked the plane and put a suspect from Germany and the air martial in the cargo hold. He held the flight attendant Sue hostage and later the whole plane. He ordered Scott Evans to land the plane later.
- Wallace Family: Ray, Jillian and Scott Wallace were all held by their neighbor and terrorist Ahmed Amar. Ahmed was injured by an attack from Stan, so he made Ray deliver a package to an address and released Jillian in exchange. The package was a nuclear bomb and it detonated in Valencia, killing Ray and about 12,000 others. Ahmed was killed in a shootout with Jack and Curtis.
- Hamri al-Assad: Held by Curtis Manning at the Granada suburb. Jack shot his friend Curtis and Assad was released.
- Hamid Al-Zarian: Held hostage by Tony Almeida and Cara Bowden, to force his brother into helping release a biological agent into Washington Center Station.