The Coronation Street actress, 32, was thrilled to tell her fans that she and Sylvain were taking the next step in their relationship after two years of dating.
Alongside emoticons of a heart, bride, top hat and ring, Samia tweeted: "'So @slongchambon and I have some more happy news to share!... #soexcited xxx."
She also shared a snap of a sparkling engagement ring on her wedding ring finger!
French Sylvain replied with the message: "@realsamia great manicure baby #shesaidOUI."
Fans rushed to congratulate the pair, with one gushing: "WOOHOO!!! Amazing news you fabulous couple! xxxxx."
Co-star Catherine Tyldesley wrote: "Yeyyyyy!!! Congrats momma!!! Awesome news xxxxxx."
The couple met when Samia competed on Dancing On Ice in 2013 and was paired with man mountain Sylvain.
At the time, he was dating his previous skating partner, Hollyoaks' Jennifer Metcalfe, while Samia had recently split from Corrie co-star Will Thorp.
In March, Samia and Sylvain announced they were expecting their first child together.
She tweeted: "Me and Sylvain have some very happy news to share… We are having a baby!! Freya can't wait to be a big sister later this year!"
Samia, who plays Maria Connor in the ITV1 soap, has a five-year-old daughter, Freya, from her first marriage to Matthew Smith.
A huge congratulations!
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