The actor will portray Scott, the younger brother of Reagan (Christina Applegate), reports Entertainment Weekly.
Scott - a laid back contractor - is described as a stark contrast from his sister, a very organised television producer.
He is also newly divorced and has a 5-year-old son who is allowed to do whatever he wants, which terrifies Reagan.
Scott, however, is liked by his brother-in-law Chris (Will Arnett).
The sitcom was renewed for another season this May, along with Parks and Recreation and Whitney.
Up All Night will return for its sophomore run on Thursday, September 20 on NBC.
