The Annex is a two-story, front gabled historic house located in Magnolia, Mississippi. It was built in the 1880s in the Queen Anne style. Although the architect is unknown, it resembles houses and commercial buildings in New Orleans that were built around that time. Magnolia and New Orleans were connected by railroad lines so the inspiration for the building's architecture probably comes from the Louisiana city. The building served as and adjunct structure for the Excelsior Hotel, which no longer exists, as a showplace for drummers who were staying at the hotel. Not much other information appears to exist about the house. It was placed on the National Register of Historic Places in 1984.