Rhiannon is obliquely referred to by her granddaughter Riley at the end of "Girl Meets 1961", an episode centering on Rihannon's mother, Rosie McGee.

Jason Marsden (Jason Marsden), Eric's best friend from the age of three. He is often more calm than Eric, and can either be his voice of reason or the one who gets him into trouble. He is quite fond of girls, as is Eric. He was on the show from 1993–1995; he left the show after graduating and going to college, leaving Eric at home to be a "townie", and was never referenced again. He was the only character on the series to have the same exact name of the actor portraying him.

Janitor Bud (Bob Larkin), the high school janitor, who later becomes Mr. Feeny's secretary due to Cory's getting him fired from his janitorial duties. After the change is made, he never appears on the show again, though he is referred to in an episode in a later season. He was on the show from 1994–1997.

When Danny McNulty left the show at the end of season 2, Griffin "Griff" Hawkins (Adam Scott) stepped in briefly as his replacement. A far different sort of bully than Harley. While much friendlier, Griff was a smooth-talking freeloader who used his wits and charm to weasel his way out of many an obligation and punishment. He was on the show from 1995–1996.

Lila Bolander-Feeny (Bonnie Bartlett, william Daniels' real-life wife), Dean of Pennbrook, who later begins a romantic relationship with Mr. Feeny. She was on the show from 1997–1999.

Chet appears as a ghost in four episodes, "Road Trip" in Season 6, as well as "Family Trees", "Brave New World (Part 2 – Series Finale)" in Season 7, and "Girl Meets Hurricane" in Girl Meets World’s Season 2. He acts as a spirit guide for Shawn in the hard times portrayed in the first two episodes, giving him counsel and advice. His appearance in the series finale is a comical one; in a moment played for laughs as he otherwise proudly watches over his sons, Chet is outraged when he hears Jack deciding to give up his wealth for happiness, but is later proud after knowing that he is joining the Peace Corps. Unlike his other ghost appearances, no one can see or hear him in this scene, so Jack is unaware of Chet's reactions.

Despite Jack resenting his father for his past alcoholism, he also wants to have relationships with him and Shawn, which leads him to choose Pennbrook in hopes of becoming close to them. Dialogues imply that though Jack has a good relationship with his stepfather, but never as close as Jack would like with his father. Jack's aversion to his family's alcoholism makes him vow never to drink, and tries to save Shawn from it in one episode. However, despite having been raised by his stepfather, Jack had a gambling problem—a trait he shares with his father, but falls into brief relapse when placing a school bet. When Chet visiting his sons at Pennbrook, he is beginning to reconcile with them before his death, leaving both Jack and Shawn devastated.