The Portage Theater's interior features a megaphone-shaped auditorium based on a formal Beaux-Arts opera house design.

When the theater was taken over by Balaban and Katz in 1940, its marquee, entrance lobby and foyer were redecorated in a sleek, streamlined art deco style to complement other prominent art deco designs at Six Corners such as Sears department store and the Klee Brothers building.

The Portage remained a popular fixture of the neighborhood, becoming a second-run movie house in the 1960s.

In the 1980s, the theater underwent a dramatic change when a wall was constructed down the middle of the existing auditorium, resulting in two oddly-shaped cinemas.

The theater was restored and renovated, and reopened after a five-year hiatus in the spring of 2006 as a single-screen, 1300-plus seat theater showing both silent and sound classic motion pictures as well as hosting other live events.