BT is launching a new free service that will stop millions of nuisance calls.
The telecom giant said it will use huge computing power to analyse large amounts of live data that will enable it to create blacklists.
Network experts will identify rogue numbers which will be diverted to a junk voicemail box. BT predicts this will block up to 25 million unwanted calls a week.
Latest figures from consumer group Which? show that three out of four people still receive unwanted calls in a month. Calls to mobile phones have also been on the rise, with seven in 10 (72%) saying they had at least one nuisance call to their mobile in the space of a month, compared to more than half (55%) in 2013.
BT expects the service to drastically reduce the number of nuisance calls customers receive.
The service will be expanded if large numbers of customers identify troublesome numbers that they wish to divert.
Customers will be able to compile their own personal blacklist by adding individual unwanted numbers or nominating whole categories of calls they want to avoid such as international calls or withheld numbers. BT will then block these types of calls.
John Petter, chief executive of BT Consumer, said: “Nuisance calls are one of the great annoyances of modern life. Everyone will have received one. We are delighted to have made this major breakthrough. We are giving control of the landline back to our customers and removing a major hassle and grief for millions of customers.
“We have been at the forefront of equipping our customers to defend themselves against the flow of PPI and unwanted marketing calls that has become a flood in recent years.
“Now we are able to announce that we are working to identify and tackle huge numbers of those calls in the network.
“We are doing our bit. We call on other providers to up their game in the fight against this menace. They can help us to root out the malicious players they may be hosting on their own networks when we identify dodgy and suspicious calling behaviour.”
The development will allow BT to share information with industry regulators Ofcom and the Information Commissioner’s Office.
Cold callers could be fined up to £500,000 for making nuisance calls when a new law comes into force this spring.
Under the plans, direct marketing companies will have to legally display their telephone number on caller ID, helping consumers report unsolicited calls to the regulators.
The Information Commissioner’s Office imposed more than £1 million of penalties for nuisance calls and text messages in 2015. Help Direct UK, Oxygen Ltd and UKMS Money Solutions were all fined £400,000 for nuisance texts.
Meanwhile, Direct Assist, Point One Marketing, Cold Call Elimination and Home Energy & Lifestyle Management had to pay £575,000 in fines for nuisance calls.