Main as Charlie Duncan,
Bradley Steven Perry as Gabe Duncan,
Bridgit Mendler as Teddy Duncan,
Leigh-Allyn Baker as Amy Duncan,
Jason Dolley as PJ Duncan,
Eric Allan Kramer as Bob Duncan and Logan Moreau as Toby Duncan • Theodora Rebecca "Teddy" Duncan (
Bridgit Mendler), Charlie's only sister and the second-oldest Duncan sibling. Feeling that she will not be around as much when Charlie is grown, she produces and directs video diaries for her, hoping they will give her advice that will help her be successful as a teenager. She produces these video diaries at the end of every episode, and at the end of every video diary she says "Good luck Charlie". • Amy B. Duncan (née Blankenhooper) (
Leigh-Allyn Baker), Bob's wife and the mother of PJ, Teddy, Gabe, Charlie, and Toby. She works as a hospital nurse and is often portrayed as dutiful, protective and comedic. It is revealed in the
movie that she is pregnant again with her fifth child. • Gabriel B. "Gabe" Duncan (
Bradley Steven Perry), the middle Duncan sibling, being both the younger brother of Teddy and PJ and the older brother of Charlie and Toby. He is initially disconcerted by Charlie's arrival and is the last one of the family to get used to her, until his older sister, Teddy, helps him. He is a prankster and troublemaker, (a
rebellious teenager) and has a rivalry with their neighbor Mrs. Dabney, who is often the target of Gabe's pranks and stunts. • Charlotte "Charlie" Duncan (
Mia Talerico), the title character and the second-youngest Duncan sibling. She is generally portrayed as being happy, but can also be mischievous at times. Many of the Duncan family's adventures revolve around Charlie. • Robert William "Bob" Duncan (
Eric Allan Kramer), the father of Teddy, PJ, Gabe, Charlie, and Toby, and husband of Amy. He owns a
pest control company, "Bob's Bugs Be Gone". He is very loving and seems to just agree with his wife; he also was the subject to jokes about his weight particularly from his son Gabe, but he lost a lot due to being fed up. • Potty John "PJ" Duncan (
Jason Dolley), the eldest Duncan sibling. He and Teddy often fight, although they care about each other, and he usually gets along well with his younger brother Gabe. He often appears awkward, somewhat careless, and childish, but on numerous occasions has been known to be resourceful, creative, and intelligent. He has also been shown to be a good cook. He and his best friend Emmett have their own band entitled "PJ and the Vibe". In season three, PJ moves into an apartment shared with Emmett. • Toby Wan Kenobi Duncan (
Jake Cinoa and
Logan Moreau) is the youngest of the Duncan children, born in season 3.
Recurring • Ivy Wentz (
Raven Goodwin), Teddy's best friend, who is seen spending most of her time with Teddy at the Duncan's residence. She often accompanies Teddy on her dutiful, or personal, excursions. • Mrs. Estelle Dabney (
Patricia Belcher), the Duncans' strict and easily annoyed neighbor, who is often suspicious of Gabe, because his pranks and troublemaking are frequently directed towards her. • Spencer Walsh (
Shane Harper), Teddy's
on-again, off-again boyfriend throughout the series, who she begins to date in the first season. • Emmett (
Micah Stephen Williams), PJ's best friend. He has a one-sided attraction to Teddy, though Teddy constantly rejects him. Emmett accompanies PJ on the drums in his band "PJ and the Vibe", and sometimes assists PJ on his problematic excursions. • Debbie Dooley (Ericka Kreutz), the Duncans' neighbor who speaks with a strong
Upper Midwestern accent. • Beau Landry (
Luke Benward), a later boyfriend of Teddy's who works for Bob's company after moving from Tennessee. • Jo Keener (
G. Hannelius), Gabe's tomboyish bully-turned-friend. • Mary Lou Wentz (
Ellia English), Ivy Wentz's mother and Amy Duncan's friend. • Harry Wentz (
William Allen Young), the husband of Mary Lou Wentz and the father of Ivy Wentz. • Skyler (
Samantha Boscarino), Teddy's friend and PJ's girlfriend. • Jake (
Tucker Albrizzi) is Gabe's empty-headed best friend. • Toby Duncan (Logan and Jake Moreau), the fifth and youngest Duncan sibling. • Karen (
Brooke Dillman), Amy's boss at the hospital, who she holds a feuding relationship with. • Vern Hardy (
Frank Collison), an employee at Bob's Bugs Be Gone and a friend of Bob. At work, Bob usually likes to tell him about his family. In Rat-A-Teddy, it is mentioned that Vern quit and started his own extermination company. ==Production==