A joint scheme involving Police Scotland and the banking sector prevented almost £5.5m of fraud last year, according to the force.
The so-called Banking Protocol scheme also saw 19 arrests made.
The system was set up to identify and protect potential victims of fraud quickly.
Police said most of the potential victims were over the age of 65, with scams ranging from romance fraud to rogue traders.
The system resulted in 815 emergency calls being logged by bank staff in 2018 that were responded to by Police Scotland.
The protocol kicks in when bank staff suspect a customer may be about to fall victim to a scam - often when they ask to withdraw an unusually large sum of money.
The bank alerts the police with a 999 call, and officers attend the branch with a guaranteed priority response.
Assistant Chief Constable Steve Johnson said: "The Banking Protocol has generated real tangible benefits to assist the most vulnerable members of our communities.
"Through the commendable efforts by the banks involved in the protocol and the actions of the police officers responding, we have ensured that banking customers in Scotland have been protected from nearly £5.5m of fraud in 2018."