Ashmore's twin brother Shawn appeared on Smallville in earlier seasons, and he was offered the role of Jimmy Olsen by director Bryan Singer in Superman Returns before Sam Huntington was cast.

[8] In 2010, Ashmore starred as Marcus, one of three journalists who investigate a cult said to practice human sacrifice in a small town in Poland, in the horror film The Shrine.

[10] In 2011, Ashmore joined season three of the Syfy series Warehouse 13, in which he played the role of ATF agent Steve Jinks, a human polygraph of sorts, who has the unique ability to discern whether someone is lying or not.

[11] Ashmore next starred in the 2014 rom-com thriller I Put a Hit on You as Ray, a man whose girlfriend tries to have him assassinated after he rejects her marriage proposal.

Aaron and his identical twin brother Shawn (also an actor) were born in Richmond, British Columbia,[2] the sons of Linda, a homemaker, and Rick Ashmore,[17] a manufacturing engineer.