It happened just before 2:00pm at the Citizens Bank inside a supermarket at the intersection of Cottman and Bustleton Avenues.
Investigators say the man gave the teller a note then fled on foot with the cash.
Anyone with information is asked to call the FBI at 215-418-4000 or the Philadelphia Police Department.
The man is considered armed and dangerous. He is described as a white male in his early 20's, 5'8" to 5'9" tall, medium build, with close cropped sandy brown hair, scruffy facial hair, wearing a black hooded sweatshirt.
There may be a reward for information leading to this subject's capture, and tipsters can remain anonymous.
