Retail and finance call centre phone scamming in the US is up 30 percent according to research.
The 2014 findings are based on some 86 million scam calls a month picked up by Pindrop Security in which attackers aimed to obtain personal information on potential victims.
The phone security company says one in 2200 calls are fraudulent up from one in 2900 in 2013, topping US$9 million a year.
The outfit's annual report (PDF) says that credit card processors have received the highest number of fraud calls and notes that regional legislation had no effect on the instance of crime.
"Rates of phone fraud are similar across economically developed countries, regardless of security regulations and legislation in place," the report states.
"Phone channel assailants use multi-pronged attacks, targeting consumers,retailers, and financial institutions simultaneously.
"Credit card issuers face the highest rate of fraud calls, with one fraud call per every 900 calls."
Scammers are increasingly using VoIP and robo-dialers to mask incoming phone numbers and better target consumers.
It says an astonishing one in six phone numbers placing consumer calls is a robo-caller with the bots calling some 2.5 per cent of phone numbers a week.
Technical support scams are unsurprisingly the most common type of phone fraud scam chalking up eight million calls a month, followed by small credit loans, and automotive insurance.
The report says brokerages which hold the highest account values are fleeced an average of $15 million annually, while credit card issuers follow with 11 million, and banks trailing at $7.6 million. ®