Saatchis fought off competition from Ogilvy & Mather and the Standard Life incumbent, The Leith Agency, to secure the financial services project.
The agency has been appointed to work on Standard Life's demutualisation campaign, which is due to run later this year. The building society is looking to heavily promote demutualisation after an attempt to convince its members two years ago failed.
Standard Life's new campaign is likely to focus on TV and press advertising. MediaCom will plan and buy media after winning the account last week. It triumphed in a competitive pitch against Standard Life's incumbent media agency, Feather Brooksbank.
The appointment of Saatchis and MediaCom does not affect the incumbent agencies' hold on their existing Standard Life accounts. The Leith Agency and Feather Brooksbank will continue to work with Standard Life but the spend on their portions of the business is likely to be reduced while the demutualisation campaign is running.
A Standard Life spokesman said: "We can confirm that Saatchi & Saatchi is working with Standard Life on a project to develop some creative ideas to support our business objectives."
Saatchis was unable to comment on the appointment as Campaign went to press.