The series three premiere date was confirmed by the broadcaster today (September 5).
Created by Oscar-winning screenwriter Julian Fellowes, the first series of Downton Abbey premiered on ITV1 on September 26, 2010.
A second series screened a year later and a Christmas Special followed.
The ensemble cast features Hugh Bonneville as Earl of Grantham Robert Crawley, Maggie Smith as the Dowager Countess and Jim Carter as valet Charles Carson.
Fellowes and the cast screened preview footage of the third year of the show earlier this year and said that financial woes and the Troubles in Ireland would dominate the series.
Shirley MacLaine has been cast as Lady Grantham's mother Martha Levinson for the upcoming episodes.
Downton Abbey 2011 Christmas Special - photo gallery