|First appearance||Sea Tunt: Part I|
|Voiced by||Eugene Mirman|
Cecil Tunt is a member of the Tunt family, Cheryl's brother, and only surviving relative. As such he is entitled to inherit half of the Tunt family fortune of one billion dollars, and is currently in charge of maintaining the trust fund containing their inheritance. Cheryl avoids speaking to Cecil and describes him as disgusting. He is in a relationship with Tiffy, whom Cheryl describes as a "brother stealer."
Cecil's first appearance in the series is in "Sea Tunt: Part I." His appearance changed drastically from his portrait in the Tunt Mansion; in "Sea Tunt" he has no beard, no red/auburn hair he has gained some weight. Cecil is apparently a vegan. He is revealed to be overly philanthropic, which makes him a terrible businessman. Several of his charities are useless/poorly conceived ("One Laptop per Child Soldier" became one thousand laptops per warlord).
In "Sea Tunt: Part II" it was revealed he gave Murphy an incredibly large salary three years in advance, a move that led Murphy to describe Cecil as "the world's worst negotiator." Cecil also approved the budget for the $200 million underwater research facility without reading it, a facility that by Murphy's own admission produced very little research of any scientific value.
Cecil's fortune was restored (and then some) with the destruction of the underwater research facility, which was insured for three times its value.
- Eugene Mirman voices Cecil. Mirman is the voice of Bob's son on Bob's Burgers. H. Jon Benjamin, the voice of Sterling Archer is also the voice of Bob. Kristen Schaal voices Tiffy, Cecil's girlfriend, as well as Bob's daughter on Bob's Burgers.
- Cecil's change in character design was done to better match his voice actor Eugene Mirman's physical appearance.