Web design and development firm Electric Pulp has taken the last available office space at Washington Square.

The company leased the final 3,600 square feet in the downtown building, which will open for its first office tenants before the end of the year.

Electric Pulp plans to move in March. It has 16 employees,with 10 based in Sioux Falls.

The firm is located at 4901 S. Isabel Place. It was founded in 1996 and has grown to work with global brands including Ford Motor Company, Google, Lexus, Acura, HP and The World Bank.

Washington Square’s other office tenants include LG Everist, Maroon Trust and Vanguard Hospitality.

The other floors of the eight-story building are condominiums, an owners’ terrace, retail space and parking.