The actress and royal, who is married to married to Lord Frederick Windsor, appeared on Monday's episode of Lorraine when she hinted that a series two was confirmed.
After discussing the Peep Show star's recent home-schooling campaign, Lorraine said: "It's a fantastic idea it really is, also I know things are on hold as far as your career goes, but I know you're going to be in Sanditon, and there are loads of things going on that I want to talk to you about [on the show]".
WATCH: Lady Frederick Windsor hints that Sanditon series two is happening
Sophie, who plays the role of Lady Susan, then responded coyly: "I'm not allowed to officially say!"
Fans will no doubt be overjoyed with the news after the ITV period drama, which also stars Rose Williams and Theo James, was initially cancelled after series one premiered in 2019.
At the end of 2019, a spokesperson for the show said in a statement to the Radio Times: "We loved Sanditon and we were very proud to have it on ITV.
The actress and royal plays Lady Susan in the period drama
"We would have loved it to return, but unfortunately we just didn't get the audience that would make that possible for us, which is heartbreaking for everybody involved in this wonderful adaptation. Sanditon is yet to air in the US and we hope they may find a way of continuing with this series."
However, the following year, Amazon Prime then teased that they could be the giants behind the renewal, tweeting to fans: "#SaveSanditon Squad, we hear you and we're doing what we can. Please could you retweet this to let us know how many of you there are so we can make a case for a new season? P.S. Don't use multiple accounts or we'll get in trouble."
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