The woman received a phone around lunchtime on Friday from a man who claimed he was calling from a telecommunications operator.
Following a method similar to others seen in telephone scams which target the elderly, the man is reported to have informed the woman that she had unused discounts and was required to log on to her online banking in order to activate them.
“He must have been persuasive, given that he convinced her to log on to her online bank,” Uppsala Police press spokesperson Linda Wideberg told Radio P4 Uppland, who reported the scam.
The incident is now being investigated as fraud, police said.
Other recent scams in Sweden have seen fake emails and text messages which purport to be from the Skatteverket tax authority.
“Skatteverket will never ask for your account details via email or text message,” the tax agency said in a statement in June this year.