The much-loved period drama finished on the small screen in 2015 and there has been a clamour for a movie ever since.
The show's official Twitter account revealed it's finally happening.
A post read: "Welcome back to Downton! We’re thrilled to announce that #DowntonAbbey is coming to the big screen. Film production begins this summer."
Joanne Froggatt, who starred as Anna Bates in all six series, expressed her excitement at the news, tweeting a picture of her and co-stars Michelle Dockery and Maggie Smith, with the words: "Delighted to announce we’re getting the band back together! #DowntonMovie #DowntonAbbey."
When asked about the film previously by The Sun, she said: "I'm sure [creator] Julian's [Fellowes] script will be just as wonderful as the series.
"You want it to carry on at the same level that we left it."
Downton, created by Julian Fellowes, first aired on ITV on 26 September 2010 and ran until December 2015.
The series, set in the fictional Yorkshire country estate of Downton Abbey between 1912 and 1925, depicts the lives of the aristocratic Crawley family and their domestic servants in the post-Edwardian era.
Historical events throughout the series include news of the sinking of the RMS Titanic in the first series, the outbreak of the First World War and the Spanish influenza pandemic.
The final season introduced the rise of the working class during the interwar period and hints towards the eventual decline of the British aristocracy.
It's expected that the movie will focus on the lead into World War Two. The sixth and final series of Downton Abbey was set in 1925, after Hitler had released Mein Kampf but before he had seized control of Germany.
While the series finale showed the beginning of the end for the British aristocracy, the upcoming movie could show the impact of the Wall Street financial crash in 1929