Cabello, 22, wore an oversized tie-dye hoodie with jeans for the outing, while Mendes opted for a white sweatshirt with black pants.
The pair has been seen packing on the PDA in recent weeks — including on Mendes’ 21st birthday on Thursday — but have yet to confirm their relationship.
“Happy birthday to this magic human, I love you!!!! ❤️,” Cabello wrote alongside a polaroid, which shows Mendes sweetly fixing her hair.
The post came after Mendes and Cabello were spotted leaving Jack’s Wife Freda bistro in New York City on Thursday, and after he celebrated his major milestone birthday by renting out a hotel near New York City’s Brooklyn Bridge. Cabello was also in attendance at the party.
Rumors of their relationship began to fly following the debut of their steamy music video for “Señorita” in late June.
The musicians have been friends for years, and also collaborated on the song “I Know What You Did Last Summer” in 2015.
While vacationing in Miami at the end of July, the singers were again spotted kissing in the water. They were later seen holding hands as they wandered along the boardwalk enjoying the summer weather.
In a recent interview with Variety, Cabello talked about collaborating with Mendes on “Señorita,” saying, “I’ve known Shawn for such a long time and it’s so much fun getting to work and do things with somebody who means a lot to you.”
In addition, the former Fifth Harmony member discussed her upcoming album and revealed she wrote it while she was “falling in love” — seemingly referring to her ex-boyfriend Matthew Hussey, whom she split from in June after more than a year of dating.
“Falling in love is like an infinite amount of levels and layers and angles,” Cabello said. “I fell in love and just opened up. Everything was written in present moment.”