It follows a survey by the company, which supplies 40 per cent of the UK’s landlines, which recorded more than 31 million nuisance calls in a single week before Christmas, with more than 12 million of these about accident claims.
The new system, BT Call Protect, analyses call data to identify rogue numbers, typically highlighting phone numbers that make large numbers of calls.
Those calls will then be automatically diverted into a junk voicemail box.
The free service will continue to block such callers even if they change their number, which is a common tactic used by spammers.
Customers will also be able to identify other nuisance callers, by dialling in the code 1572 after receiving such a call.
The latest research carried out for BT shows that in Scotland on average people receive between four and five nuisance calls a week and 60 per cent of people in the UK said they find nuisance calls stressful. More than a quarter of people are concerned about their parents or grandparents getting nuisance calls in case they are conned. Brendan Dick, BT Scotland director, said: “This new service is great news for people in Scotland. We know that nuisance calls are a big problem for people in Scotland, who receive many millions of such calls every year. Some of these calls can be upsetting and unnerving as well as very annoying, particularly for people who are more vulnerable perhaps through age or disability.”
John Petter, chief executive of BT Consumer, said the company is “declaring war” on the companies that regularly pester its customers.
He continued: “We’re giving our customers the means to fight back against the millions of unwanted calls for free.”