The basement floor is concrete. The walls and ceilings of the three main floors are of plaster, although some of the offices have modern wood paneling. Marble wainscoting extends along the walls of the first and second floors and in the stairwells. On the first floor the corridors have covered barrel vault ceilings. Plaster Sullivanesque decorated raibs between the coffers extension down the walls to pilasters capped with plaster Corinthian capitals.
Pilasters also occupy the intersections of the angles of the octagonal rotunda.
The arched openings leading into the rotunda have Sullivanesque plaster decorations on the laces and soffits of the arches. On the third floor the plaster arch over each face of the octagon has Sullivanesque decoration and an ornate shield at the keystone. The dome over the rotunda is art glass with decorated plaster ribs. A large light fixture hangs from the center of the dome. It has a center frosted glass shade and twelve branches which also have frosted glass shades.