In addition to performing with The Second City improv group in Toronto and Los Angeles, Oldring has appeared on Canadian television. He was also a regular cast member of the redneck-themed sketch comedy series Blue Collar TV. Feature film roles include K-19: The Widowmaker, Focus and Lost and Delirious. He has a starring role in Intern Academy. He also played Farrah Fawcett's gay assistant in the television movie Hollywood Wives. Oldring also appeared in the series Doc and The WB's D.C., as well as in the television movie The Ricky Nelson Story.
Oldring voiced Cody, Ezekiel and Tyler in Total Drama. In 2011, he was cast as "Lonnie" in the Disney XD show Kickin' It. He had a supporting role in the premiere episode of the 4th season of Psych, "Extradition: British Columbia." His voice acting credits include the animated children's show Braceface, Mischief City, Miss Spider's Sunny Patch Kids, My Friend Rabbit, Pelswick, Total Drama, 6teen Pecola and Glenn Martin, DDS. Oldring has also voiced video game characters, such as Alfred Ashford in Resident Evil: Code Veronica X. Oldring has also worked on numerous projects with his longtime creative partner Pat Kelly, including The Comedy Network series Good Morning World and the CBC Radio comedy show This Is That. Oldring currently appears on the TVOne original series Love That Girl! as a gay hairdresser named Fabian.