Test Building, Historic building in Indianapolis, United States.

The Test Building is a nine-story reinforced concrete building completed in 1925 in the Neoclassical Revival style by Bass, Knowlton & Company. Its curtain walls of 12-inch brick and clay tile are faced with Indiana limestone, and it has a three-story brick penthouse above a two-level basement.

The Test Building was built in 1925 by Bass, Knowlton & Company in the Neoclassical Revival style. It was first planned as a parking garage with ground-level stores, but the plan drew controversy over danger to pedestrians and traffic congestion. It was listed on the National Register of Historic Places in 1983 and lies within the Washington Street-Monument Circle Historic District.

The building's name comes from the Test family, whose Test Motor Inn occupied it; locals also know it as the Circle Motor Inn. Its ground-floor storefronts and multi-level parking decks show how 1920s Indianapolis combined retail and the automobile in one block.

The building stands at the corner of Washington Street and Monument Circle in downtown Indianapolis, within the Washington Street-Monument Circle Historic District. Its two-level basement and three-story brick penthouse shape the structure a visitor sees from street level. The upper floors are not a public museum, so viewing is from the exterior and the surrounding district.

The building was first planned as an all-parking structure with ground-floor shops, but the plan drew controversy over danger to pedestrians and traffic congestion. Its curtain walls are 12 inches (30 cm) thick, combining brick and clay tile behind the Indiana limestone facing.