Get our money-saving tips and top offers direct to your inbox with the Mirror Money newsletter Sign up Thank you for subscribing We have more newsletters Show me See our privacy notice Invalid Email

Most broadband providers have been forced to cut their advertised speeds following a recent rule change to prevent misleading claims, a consumer group has found.

Which? analysis of the biggest broadband providers found that 11 have had to cut the advertised speed of some of their deals since the new rules came into effect in May, with the cheapest deals dropping by an average 41%.

BT, EE, John Lewis Broadband, Plusnet, Sky, Zen Internet, Post Office, SSE, TalkTalk and Utility Warehouse previously advertised their standard broadband deals as "up to 17Mbps" but the new advertised speed is now more than a third lower at 10Mbps or 11Mbps, Which? said.

Under the tougher rules, home broadband providers must now ensure that at least 50% of their customers can achieve advertised speeds at peak time.

(Image: Getty)

They had previously been allowed to advertise "up to" speeds as long as they were available to a minimum of just 10% of customers, resulting in widespread complaints from Government, consumer groups and the public.

Which? found that across all the deals on offer from the 12 biggest providers, the advertised speeds from "up to 17Mbps" to "up to 100Mbps" had decreased by an average 15%.

Only Virgin Media's advertised speeds had gone up since the change.

Before the new rules came into effect, Which? found evidence that British households were paying for broadband services that were on average 51% slower than advertised.

Alex Neill, Which? managing director of home services, said: "Customers will now have a much clearer idea of the speeds that can be achieved when they are shopping around for broadband.

"For those still struggling to get a reasonable speed or connection, the Government must press ahead with its crucial plans to deliver the service that broadband customers need, without it costing them the earth."

A National Infrastructure Commission spokesman said: "Today's findings demonstrate the slower broadband speeds that households and businesses are actually working with. But if we are to make a lasting difference, as well as tackling the immediate issues, we need to invest properly for the future.

"Our National Infrastructure Assessment, the first of its kind for the UK, endorses a move to full fibre broadband which could help guarantee that customers get the speeds they pay for - as much as 1,000Mbps."

A TalkTalk spokesman said: "We welcome the efforts to simplify broadband speed claims. While average speeds are a useful guide, what customers really want is a guaranteed speed specific to their home.

"We already provide that at the point of sale, meaning customers can be certain about the speeds they will receive before they buy the product."