It happened around 6:40 Friday night on the 1100 block of North Bethlehem Pike.
Authorities say a man entered the Bank of America branch inside the Giant grocery store.
The suspect presented a demand note and indicated that he was armed with a gun, though none was shown.
After receiving an unknown amount of cash, the bandit fled the scene.
The suspect is described as a white man in his 30s, about 5'10" to 6'0" tall with a medium build. He was last seen wearing a red Phillies cap and a black jacket.
Police believe this same suspect robbed a Jimmy Johns sandwich shop in Upper Dublin on Thursday and a Saladworks in Horsham on Monday.
No one was injured in any of the incidents.
Anyone with information is urged to contact police immediately.