Underwood, 30, is engaged to political strategist Jordan C. Brown, 39.
Underwood revealed the news first to PEOPLE.
He tweeted and posted on Instagram, "Life is going to be fun with you!"
life is going to be fun with you ♥️ pic.twitter.com/21Kd21u0tS— coltonunderwood.eth (@colton) February 28, 2022
Brown shared on Instagram, "The only time in my life I'm ok with wasting a bottle of champagne. I love you babe."
Underwood came out as gay publicly less than a year ago in April 2021.
Before Underwood had the starring role on "The Bachelor," he was vying for Becca Kufrin's heart on "The Bachelorette" back in 2018. As a fan favorite, and Becca's final 4, he was offered a spot on "Bachelor in Paradise" and then "The Bachelor."
As the season 23 "Bachelor" he fell in love with Cassie Randolph and famously, "jumped the fence" for her. His virginity was brought up continuously throughout the show. "I loved everything about her," he said.
Underwood and Randolph dated for the next year, but never got engaged. They broke up in 2020 and Randolph filed a restraining order against him. In a police report, she accused him of putting a tracking device on her car. She later dismissed the restraining order.
Previous relationships also included Tia Booth on "Bachelor in Paradise" and Olympic gymnast Aly Raisman.
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