BT is offering its customers the chance to boost their broadband speed at no extra cost by using its Broadband Accelerator tool.

The accelerator is a small plate that customers who have more than one phone socket can use to reduce the impact of electrical interference. This interference can degrade people’s broadband speeds significantly. BT said using the plate can increase speed by up to 1.5Mbits/sec.

The move to improve speed comes after Ofcom criticised internet service providers of misleading speed claims. The telecommunications regulator published research in July that found broadband customers are still being sold speeds that few of them will get.

Ofcom said its study of services advertised as ‘up to’ 8Mbits/sec, found significant mismatches between what ISPs advertise and what people receive. It said fewer than one in nine people are getting anywhere near the headline speeds advertised.

BT said with the launch of its faster headline speeds of up to 20Mbits/sec people who are having problems with slow connections may improve speeds by using the accelerator; also known as the I-Plate.

John Petter, managing director of BT’s Consumer division, said: “We think it is so important we’ve taken the decision to offer it to our customers for just the cost of the postage (£1.20).

The I-Plate, normally costs £15, but BT is offering it free to BT Total Broadband customers who order it online.

Although BT said the I-Plate is easily inserted into a user’s main telephone socket, the package comes with an easy self-install guide. BT has also included a 10-step guide on how to optimise broadband speeds.