Thorne, a former Disney star, and Mascolo, who have been dating for two years, announced the news on their social media accounts on Sunday.
“She said yes!” Mascolo captioned his Instagram post of the couple.
Throne has a dizzying smile in her Instagram stories when she shows the ring on her hand.
“I love you so much,” she says to Mascolo, who is holding the camera.
“A party in Italy and in America,” he says at the end of the list.
Mascolo suggested on the set of a movie in which the pair star together, he said.
“I wrote the love letter on the back of our film’s script…” he wrote in his Instagram story. “At the end or the last scene she was watching the monitor with the director and … surprise.”
The couple have been romantically linked since 2019 after Throne broke up with Mod Sun.