The singer and Broadway star took to her Instagram story while going on a "socially distanced" walk through the park, and shared the surprising news.
“Just wanted to check in. I’m really quiet right now and will probably continue to be quiet," Bareilles began. "Just sort of taking all of this in and having a lot of feelings as I do."
“I had it, just so you know," she continued, sharing the news of her diagnosis for the first time. "I’m fully recovered, just so you know."
The entertainer went on to say that she's "thinking about all of the people who are walking through this really tricky time and sending a lot of love." She added that she feels "really grateful for every easy breath and every day that I get to be walking around."
Bareilles didn't reveal anything more about her illness, or how she may have contracted the virus.
Bareilles' Waitress co-star, Gavin Creel, admitted during a podcast last week that he was self-quarantining because he believed he had COVID-19.
"I haven’t been tested, but I have coronavirus… I found out because one of my castmates from Waitress tested positive and I have every symptom, but I feel good," Creel said at the time. "I’ve been staying inside. I’ll be inside for the duration."
Creel and Bareilles acted together in their final performance of Waitress on March 14, before all of Broadway was shut down as part of the city's efforts to slow the spread of the outbreak.
See the video below for more on the outbreak and stars who have also shared their own coronavirus stories.