PopUp Bagels, the viral bagel chain that is on its way to the Philadelphia area, will preview its arrival with a one-day pop-up event Sunday at Di Bruno Bros.’ flagship store near Rittenhouse Square.

PopUp will take over Di Bruno’s second floor from 9 a.m. to 1 p.m., offering an early taste of its “grip, rip, and dip” bagels — and a limited-edition collaborative schmear — while raising money for charity.

» READ MORE: Not everyone loves PopUp Bagels

PopUp’s location in Suburban Square in Ardmore, across from Shake Shack, is due to open in February.

Bagels will be available by preorder only, with sales launching Monday on popupbagels.com. Franchisee Brian Harrington said 300 dozen bagels would be available at Di Bruno’s, 1730 Chestnut St.

Harrington said that for one of his new stores in Boston earlier this year, PopUp tied a preview to the Boston Marathon. “We put them online for preorder and they sold out in 16 minutes,” Harrington said. As people arrived for their bagels (six for $24), they were feted with music and PopUp swag to stimulate buzz.

PopUp, conceived in a Connecticut backyard in 2021, does not make sandwiches or even offer sliced bagels — rather, the bagels are sold hot and whole with cups of cream cheese “schmears” or butter for dipping.

In Philadelphia, customers will be able to preorder a six-pack of mixed bagels — plain and everything flavors — along with classic plain and scallion schmears. The highlight will be a third schmear: a limited-time-only collaboration blending Di Bruno’s Abruzzi cheese spread with PopUp’s classic cream cheese.

All proceeds from the day will benefit the Eagles Autism Foundation and the Travis Manion Foundation.

After Ardmore, PopUp is planning for three locations in the Philadelphia market in 2026 and as many as seven or eight overall in the longer term.

PopUp Bagels was launched during the pandemic by Adam Goldberg, a bored flood-mitigation specialist who started baking sourdough bread at his home in Westport, Conn. He turned that into a bagel recipe, settling on a light, soft bagel, as opposed to the chewy New York style. The backyard project drew attention and led to pop-up shops in New York City.

Social media attention and investors quickly followed. Fans of the chain line up outside locations across Connecticut, New York, and Massachusetts to film TikToks of them ripping apart bagels and dipping them into cream cheeses.