| Description | Character |
| Appeared in 53 Episodes was in seasons 4, 5 and 6. | |
| Was the Secretary of Defense under President John Keeler | |
| Appeared in Seasons 7 as FBI Agent and Season 8 as an Undercover Operation was killed | |
| CTU Head Analyst Husband appeared in 29 Episodes | |
| Portrayed By James Morrison appeared in 64 Episodes | |
| Chief of Staff for Senator in Season 1 | |
| In Season 6 the CTU Agent who was Killed by Main Character when holding terrorist hostage | |
| CTU Director of Field Operations Season 8 | |
| President in Season 6 gets severely injured | |
| Former wife of Season 2 President | |
| CTU analyst who was brought back in season 6 after appearing in season 1 | |
| Season 3 analyst who is killed when Cordilla Virus in released in the hotel. | |
| Worked for the President of Season 7 and 8 as Secretary of Homeland Security | |
| Responsible for the death of question #7 appeared in season 5 for 11 episodes | |
| Worked for CTU and married question # 23 character | |
| Was the Secreatary of defense for the President in season # 6 and White House Chief of Staff for the President in season 7 and 8 | |
| Appeared in 25 episodes. Was in seasons 2 and 3, also played main character's love interest. | |