This Mission Revival building has a scrolled, parapet gable and a quatrefoil vent in the attic. The clerestory has an unusual X-muntinned design. This is a superb example of a style uncommon to Eureka and part of a row of small-scaled, diversely styled but highly compatible buildings.

Originally constructed in the 19th century, the Cousins building received a 20th century façade after a fire in 1905. This façade is eclectic in composition. The scroll parapet reflects the Mission Revival style while the first-floor elements are Classical Revival.

The Cousins Building contributes to the Eureka Old Town Historic District which was listed on the National Register of Historic Places in 1991.