Curse of the Lake Monster (2010), The Hunters as Paxton Flynn (2013), The DUFF as Wesley Rush (2015), The Babysitter as Max (2017), and the science fiction film Code 8 as Connor Reed (2019); the latter of which also starred his cousin, Stephen Amell.

He also appeared on television shows such as Life with Derek (2006–2008), True Jackson, VP (2008–2011), Unnatural History (2010), and Revenge (2011–2012).

At age sixteen, he began landing roles in high school plays such as Louis and Dave and Fionia, Picasso at the Lapin Agile and The Importance of Being Earnest.

Amell had a role in the Canadian Family Channel series Life with Derek, playing lead character Casey McDonald's boyfriend Max.

He played the role of Noel Kahn's brother Eric on the ABC Family television series Pretty Little Liars during the show's third season.

[12] In 2013, Amell received his biggest role to date, lead character Stephen Jameson in CW's sci-fi drama The Tomorrow People, a remake of the British series of the same name.

[17] Amell starred alongside Kevin Spacey and Jennifer Garner in Nine Lives, which was released on August 5, 2016.

[24] Amell's performance was cited as a highlight of the series, particularly his chemistry with co-star Andy Allo and when playing dual roles in the third season.

[25][26][27] Amell began dating actress Italia Ricci in July 2008 after meeting her while filming American Pie Presents: Beta House.