The on-off couple was seen spending the holiday with friends in downtown Philadelphia
During a New Year’s Eve outing in downtown Philadelphia — where Simmons, 23, plays for the local 76ers NBA team — Jenner, 24, walked alongside her ex and a group of friends to a private party at the rooftop bar Attico, according to TMZ.
The sighting comes months after a source told PEOPLE that the on-off couple was “on a break” in May.
“The relationship ran its course,” the insider said at the time. “She’s spending time with her friends and back to being in fun mode.”
Since their split, Jenner and Simmons have seemingly maintained a friendly relationship and have continued to interact with each other.
In August, both Jenner and the basketball player attended a birthday party, along with Jenner’s sister Kourtney Kardashian and her own ex, Younes Bendima, with whom she rekindled a romance last month.
More recently, Jenner was spotted cheering on Simmons at one of his games in Philly in December, nearly seven months after calling off their relationship.
Jenner confirmed that she had been dating Simmons during an appearance on The Ellen DeGeneres Show in February.
“So obviously you’re dating this guy who’s on the 76ers. How long have you been dating him?” host Ellen DeGeneres asked, before she replied with a huge smile on her face, “For a bit now.”
That same month, Simmons and Jenner stepped out for an early Valentine’s Day date in New York City. Jenner later opened up to Vogue Australia about their relationship, as well as the possibility of marriage.
“Maybe. Definitely not now, but maybe one day,” Jenner told the magazine. “I got a glimpse of how my sisters dealt with [the attention] and it’s cool to learn from that.”
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The Keeping Up with the Kardashians star also revealed why she chose to keep her relationship with Simmons private.
“For me, a lot of things are very special and very sacred, like my friends and relationships, and I personally think that bringing things into the public makes everything so much messier,” she said at the time.
“I’m very young, and right now I feel like relationships aren’t always super-certain and I don’t want to bring too much attention to something if you don’t really know long term [what it’s going to be],” she told Vogue.
She added: “A relationship is only meant to be between two people, and the second you make it the world’s business is when it starts messing with the two people mentally. Like once everyone is let in, you’re letting all these opinions into your relationships, and I don’t think that’s fair.”
At the time of the interview, Jenner appeared to be very much committed to Simmons. She FaceTimed the basketball star before sitting down with Vogue and even streamed his game while sitting in the hair and makeup chair, according to the publication.