The Sterling Savings Bank branch on West Stewart Avenue was robbed for the third time in almost five months on Friday.
Medford officers are still on the lookout for the suspect.
The robbery was reported at about six in the evening.
Police said a man robbed the branch and then took off.
No weapon was seen or mentioned during the robbery.
Police describe the suspect as 5'9", 190-pounds, olive complexion, wearing a dark blue hooded sweatshirt and jeans.
The branch was the site of two previous robberies, one in September and the other in December of 2012.