The "That '70s Show" stars are said to have tied the knot over the weekend, according to People, which first reported news of the nuptials on Sunday.
Few details were readily available, and reps for Kunis and Kutcher did not immediately respond to The Times' requests for confirmation.
If they indeed wed, it's the first marriage for Kunis and the second marriage for the "Two and a Half Men" actor, who was previously wed to actress Demi Moore in 2005. The former couple finalized their long-running divorce in November 2013.
Kutcher, 37, and Kunis, 31, met on the set of their groovy Fox sitcom, which aired from 1998 to 2006, and have remained friends for years. They didn't start dating until April 2012, several months after Moore announced her split from Kutcher. He popped the question to Kunis around February 2014.
The "Ted" star gave birth to their daughter, Wyatt Isabelle, last fall, and through it all, the private pair has played coy about their marital status.
In December, the tech entrepreneur shared an eyebrow-raising beach photo signed "The Kutchers" on his Facebook page, leading people to speculate that they'd already tied the knot. Kunis also wore a diamond band on her left ring finger while promoting "Jupiter Ascending" last February, which made more people think that the deed was done — including daytime host Ellen DeGeneres, who put Kunis on the spot about the sign-off in question.
The actress simply rationalized the image and expertly avoided DeGeneres' question saying, they "could just be a plural. Like, my daughter has his last name legally. So thus, there's multiple Kutchers. He has a brother," she said.
"Late Late Show" host James Corden tried to get it out of her too on his debut episode in March, but Kunis laughed off his line of questioning with an "I don't know, maybe" response in the manner that she did with DeGeneres.
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