The Voice Report surveyed more than 300 contact centre staff and reveals that more than one million customers hang up on call centres every week.
A third of the businesses questioned believe that customers hang up after spending just 30 seconds on hold.
As a result, two thirds believe they could be losing 30 per cent of potential business.
The report says the main reason behind this is that contact centres are placing more emphasis on time efficiency rather than customer service.
"Virtually all call centres measure efficiencies such as the number of calls handled per agent and length of call, rather than customer service," said Paul Wright, chief executive of Vocalis. "The ways call centres seek to achieve these aims include automated replies, or leaving callers in a queue or with an engaged tone."
He added: "Customers are demanding better service. Callers who can't get through might easily go to competitors."