Turner, 21, shared the same image, captioning it: "I said yes".
Sophie, on the other hand, opened up about her love life to InStyle UK, admitting she has "never dated anyone who I didn't know before or who's in the industry".
"I said yes", Turner captioned the photo of her gorgeous ring.
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Sophie and Joe have been dating since a year ago (16).
See the engagement announcement photo from Sophie Turner below.
"Queen! I love you so much xo". It's frustrating [that] it's the most mundane things that make the news - how boring! "Going out with friends, going out to eat, not really having a care", she told the publication.
She continued, "It really helps you own those insecurities".