The company was founded in 1999 by the pension funds of Credit Suisse and Siemens Switzerland and the then Winterthur Life . Swiss Prime Site was listed on the SIX Swiss Exchange in April 2000. At the time, the real estate portfolio had a value of around CHF500 million.In 2001, Swiss Prime Site bought a portfolio of office buildings from Swisscom. In 2003, it acquired the Frey Group and in 2004 Maag Holding AG. In 2009, the takeover of the stock listed Jelmoli Holding AG took place. In October 2012, Swiss Prime Site acquired Wincasa AG, a real estate service company in Switzerland, as well as the Tertianum Group. In 2019 Swiss Prime Site announced the sale of the Tertianum Group. At the end of 2021, Swiss Prime Site acquired the Akara Group to strengthen the Services segment.Completed construction projects: Espace Tourbillon Genf, Basler Messeturm, Opus Zug, the PostFinance Arena and Schönburg in Bern YOND and Sihlcity in Zürich as well as the Prime Tower with the Clouds restaurant and its neighboring building. The Prime Tower on the Maag site in Zürich West, is with its total of 126 meters, one of the tallest office buildings in Switzerland.
