The star – who plays Eva in the ITV soap – announced her happy news via Twitter on Sunday (30 August).
Catherine tweeted: "I have something to tell you all… So pleased to tell you all that I'm going to be Mrs Pitfield. I said YES!! Love you [Thomas]. So happy. What a year!!"
The engagement news came a week after Catherine and personal trainer Thomas revealed they are expecting their first child together.
Actress Catherine, 30, met Tom, 27, at Hale Country Club, where he was working as a trainer and she was doing gym sessions.
Catherine's engagement was greeted with a slew of congratulatory messages from her Corrie co-stars and friends including Michelle Keegan, Jack P. Shepherd, Shobna Gulati and Samia Ghadie.
Michelle gushed: "Congratulations to the both of u! What a fairytale year you've had! So lucky to have found each other."
Perhaps she and Catherine can exchange wedding tips? Michelle's currently in the midst of planning her big day with fiancé Mark Wright.
Congrats to Catherine and Tom!
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