The 25-year-old British singer was spotted kissing and holding hands with 23-year-old American actor Brandon Flynn in New York this week, according to TMZ.
Smith and the "13 Reasons Why" star were openly affectionate during a sunny outing in Greenwich Village. The pair both wore casual ensembles, with the singer in a white t-shirt and light denim and Flynn donning a striped t-shirt and black pants.
E! News reported Smith and Flynn were also seen eating at Catch NYC and dancing at the restaurant's rooftop bar Monday.
The pair went to see the Broadway hit "Dear Evan Hansen" the next day, which Smith praised on Twitter.
"Just went to see 'Dear Evan Hansen' - out of this universe. I properly snot cried throughout! @BenSPLATT was sensational xx GO SEE IT," the singer wrote.
Smith, who publicly came out as gay in 2014, had described himself as "insanely single" in an interview with Beats 1 Radio in September.
He liked an Instagram post Flynn penned the same month addressing hate amid Australia's voting period for same-sex marriage.
"Too many of my friends have been kicked out of the homes, kept in the closet, beat up, killed, ridiculed by church and state, institutionalized... and you are scared that if we vote YES, you won't be able to show your hate for Us," the actor wrote.
"We've been scared [expletive] our whole lives thanks to all the stigmas that surrounds Us," he added.
"Equality takes courage, it worries me that too many people in this world lack the balls to stand up for what is right."
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