Seagram & Sons moved into its offices in December 1957 and a temporary certificate of occupancy was granted by the Department of Buildings during 1958. The Seagram Building officially opened on May 22, 1958; at the time, it occupied some of the office space and leased the remainder out. The permanent occupancy certificate was granted by the Department of Buildings in 1959. Including $5 million of land purchases, the project was expected to cost $43 million, or about . The construction cost per square foot was about twice as high similar buildings in the city. However, Seagram vice president Arthur S. Margolin said in a 1989 interview that the cost had been approximately $40 million.