The west end of Luther Hall was built in 1925 and opened in 1926. It housed classrooms, laboratories, administrative offices, and the college library. A south addition facing Bremer Avenue was dedicated in 1952, the college's Centennial year. It effectively doubled the building's capacity and added a terraced entrance that served as the platform area for Commencement for many years. Neumann Auditorium, which opened in 1959, filled in the U-shape between the two additions. It was known as the Chapel-Auditorium until 1965, when it was renamed the G. J. Neumann Chapel-Auditorium in honor of Dr. G. J. Neumann '07. Neumann served Wartburg College at both Waverly and Clinton from 1910 to his death in 1964.

The third floor of Luther Hall was extensively remodeled in 1988 as a Humanities Center. It now houses the departments of English and modern languages and history. Some classes in these departments also take place in the Classroom Technology Center.

During the summer of 2000, the ground floor underwent renovation and now provides improved office and conference space for the Institutional Advancement Division, including Development, Alumni and Parents Programs, and Communication and Marketing.