In 2004, Aselton appeared in a short film titled Scrapple opposite Mark Duplass and his brother Jay Duplass who also wrote and directed the short. Aselton made her feature-length film debut in The Puffy Chair opposite Mark Duplass, who directed the film alongside his brother Jay. The film premiered at Sundance in January 2005 and was released on June 2, 2006, in a limited release. That same year, Aselton appeared opposite Steve Zissis in the short film "The Intervention." In 2009, After a break from acting, Aselton appeared in an episode of the The Office. That same year, she appeared in "Easier with Practice," "Other People's Parties," and "Feed the Fish." In 2016, Aselton appeared in Togetherness, an HBO original series created by her husband and brother in law, as Anna. That same year, she was cast in a recurring role in the second season of Casual as Jennifer. Aselton is also attached to star in Fun Mom Dinner opposite Molly Shannon and Toni Collette, directed by Alethea Jones.