The 37-year-old composer, who wrote the score for the hit Broadway musical, is dating actor Joe Tippett — one of the show’s current stars.
Both have made numerous public appearances together over the past few months, including the opening night for The New Group’s play All the Fine Boys in March and PEOPLE and EW’s Upfronts Party in April.
They also attended Sunday’s 2017 Tony Awards together, where they looked adorable while posing on the red carpet. He even gave Bareilles a sweet kiss on the cheek at one point — as she smiled gleefully for the cameras.
(Reps for Bareilles and Waitress had no comment).
Bareilles and Tippett, 35, first worked together on the musical adaptation of the 1997 Adrienne Shelly film during its out-of-town tryout at the American Repertory Theater in Cambridge, Massachusetts in August 2015.
A stage veteran with credits in Broadway’s Airline Highway, he played Earl, the moody husband of the story’s protagonist Jenna — though didn’t transfer with the production when it first moved to Broadway in April 2016.
Tippett’s in the part now though, having begun performances on Tuesday. Sadly, he just missed Bareilles — who completed her sold-out run as Jenna on Sunday.
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In May, Bareilles gushed about how much Waitress has changed her — making a reference to Tippett.
“My life is so different because of Waitress,” she told ABC News. “The people that I’m close to, the things I do professionally, my colleagues, my best friend and my boyfriend, like all of these things have come to me because of the show. And it’s really beautiful.”
With her role in Waitress behind her, Bareilles previously told PEOPLE she’ll next focus her time on a new album. Tippett, meanwhile, has a role in NBC’s upcoming midseason TV show Rise — about a passionate high school teacher who galvanizes his students and the town when he reinstates the drama club.
Waitress is currently playing at New York City’s Brooks Atkinson Theatre.