Platt, 29, and his fellow Dear Evan Hansen alum Galvin, 28, announced their engagement last month. Now, Platt is giving fans an inside look at the special moment as he shared sentimental snaps Monday on Instagram.
He started the carousel with a photo of him and Galvin surrounded by loved ones, following up with a sweet image of the pair embracing. The future newlyweds also posed with friends as Platt kissed a smiling Galvin on the cheek.
Platt included photos of those who joined them to celebrate the occasion; he ended the series of snaps with a picture of the actors, who have both played the lead in Dear Evan Hansen on Broadway, sharing another kiss.
"More 💍💕 thanks to all who made it special," Platt captioned the post.
The pair have been together since January 2020, after a friendship that lasted a number of years. Galvin went public with their relationship that May during an episode of the Little Known Facts with Ilana Levine podcast.
Platt later opened up about how his bond with Galvin turned romantic during an appearance on The Kelly Clarkson Show in June, explaining that he didn't realize his feelings for the actor until five years into their friendship.
"We've been together a year-and-a-half now," he said at the time. "We were friends for five years and right before the pandemic, we finally decided to really give it a shot. We kind of skated around it for a long time."
According to Platt, the COVID-19 pandemic brought things from "zero to 60," and the couple started "living together with my parents in our childhood home and seeing each other all the time."
"It ended up being a beautiful time," he added.
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Sharing photos from the proposal and highlighting the ring in November, Platt wrote in the caption, "He agreed to hang out forever." On his page, Galvin wrote, "I said yeehaw and then cried for like 7 hours."
After Platt stepped down from the titular role in the Tony-winning musical, Galvin was announced as his replacement in November 2017. The two developed a close friendship, which eventually blossomed into a romance a few years later.