Turnstone was established in 1989 in a Joint Venture with Dencora plc.

In July 2000 the company cemented a long-standing commercial property joint venture relationship with The Scottish Life Assurance Company into a corporate involvement when SLAC replaced Dencora as the company's principal shareholder.

In turn the company became a subsidiary of Scottish Life which itself was merged into the Royal London Group of Companies in 2001.

In October 2005, the Royal London shareholding was acquired by the company in return for cash (utilising surplus cash reserves) and direct stakes in certain property projects (notably the land at Waterbeach).