The "Modern Family" actress dropped the news while speaking to Dax Shepard while he filled in for Ellen DeGeneres on her show on Thursday.
While Dax admired the jewelry, he noted the Wells had "great taste."
"Thanks, I told him what to get," she said, as the studio audience cheered.
Afterward, bauble on hand, Sarah dished on how she met the reality TV veteran and soon-to-be husband.
"I saw him on 'The Bachelorette,'" she said. "And then he became the bartender on 'Bachelor in Paradise,' and I was like yeah, uh-huh… I thought he was real hot and then he slid in those DM's because I tweeted about him."
On July 16, Sarah and Wells both announced on social media that they had gotten engaged in Fiji.
Afterward, Wells spoke about the engagement on his podcast, "Your Favorite Things," saying Sarah knew a proposal was imminent. While Wells said he was certainly happy to be engaged, he was also thrilled to no longer have to lug that ring around.
"Guys, for the most part, are not used to having expensive pieces of jewelry around them," he said. "So, it freaks us out just in general. Also, for me, we were traveling across the ocean, so that's even more stress of like, 'What happens if someone steals my bag or something?' Everyone is like, 'Are you so happy?' And I was so happy but I'm also so happy I'm not in charge of that very nice ring. There's too much pressure!"