The exciting news was confirmed by the actress' publicist Marcel Pariseau to The Associated Press on Sunday, May 19.
As for the wedding plans, the publicist told the publication that no date has been set for the nuptials.
The couple was first spotted packing on PDA at an afterparty for the finale of Saturday Night Live season 42 in May 2017 and they made their relationship public in November of that year.
Weeks later, a source told media that the comedian was "telling friends he wants to marry her."
Colin previously spoke about his girlfriend to Entertainment Tonight. He told the outlet that "she’s pretty cool."
It’s hard to have a lot of complaints, she’s pretty awesome. I’m very happy. I feel very lucky.
The Tony award-winning actress, meanwhile, told Ellen DeGeneres in April 2018 that she was "a Colin fan."
Forbes Celebrity 100 star, 34, was previously married to Canadian actor Ryan Reynolds (2008 to 2011).
She tied the knot with journalist Romain Dauriac in 2014 but called it quits three years later. The former couple shares a 4-year-old daughter, Rose.
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