In 2005, Reid played the role of Darrell Fox in the made-for-television movie Terry which dramatized Terry Fox’s historic run for cancer research. In 2007, he appeared in the Naturally, Sadie episode “As the Whirly Turns”. In 2009, Reid guest-starred in the Degrassi: The Next Generation episode “Danger Zone”.

Reid’s first leading role in a feature film was Farley Gordon in Score: A Hockey Musical, which premiered at the 2010 Toronto International Film Festival. He then played several guest roles on television, including in the police drama Rookie Blue (2012) and the drama series Cracked (2013). In 2013, he also appeared in the CW web series Backpackers. In 2015, he played the lead role in the ABC Family comedy series Kevin From Work. The series was canceled after one season.

In 2016, Reid was nominated for a Canadian Screen Award for Best Original Song for his work in the feature film People Hold On (2015), in which he also starred. He also released a self-produced full-length original album, Songs From a Broken Chair.

In 2017, Reid played the recurring role of Patrick in the third season of the CBC series Schitt’s Creek. That year, he was also cast in the independent film Cardinals, opposite Sheila McCarthy, which premiered at the 2017 Toronto International Film Festival.

In 2018, Reid was promoted to a series regular on Schitt’s Creek, beginning with the series’ fourth season. He also performed in a production of Hamlet at the Tarragon Theatre in Toronto in the same year. He starred in the film Buffaloed, which was released in February 2020. Reid later embarked on a tour across North America to support his then-upcoming second album. However, a number of the original dates had to be indefinitely postponed midway through the tour due to the COVID-19 pandemic. The album, titled Gemini, was released on May 29, 2020.

Reid announced his engagement to actress Clare Stone on December 31, 2018. They were married on July 25, 2020. Reid is a dual Canadian-US citizen.