Five million households who are out of contract on their broadband could be losing out on £804m ($1.1bn) due to not shopping around.
According to new research by Uswitch.com people fail to act because they worry about losing connection or the perceived hassle of switching.
One in three (37%) households worry switching will leave them without broadband for a day, but in reality nearly three quarters (72%) see no or very little interruption, according to the research.
Uswitch found that “non-switchers” have been out of contract for 19 months on average, paying £149 more than they should have in that time.
The price comparison tool has called on Ofcom to ensure that broadband switching is comprehensively coordinated by providers. This would ensure consumers can have full confidence in a seamless switching experience, it said.
Almost half of consumers (49%) who had switched in the last 18 months found the process easier than they had expected, compared to only one in ten (10%) who found it harder.
A fifth of consumers (22%) have never changed their broadband provider, and one in ten people (10%) don’t know when they last switched their contract, despite the fact that customers whose deals have expired pay an average of £90 over the odds each year.
Richard Neudegg, head of regulation at Uswitch.com, said: “There’s still a lot of work to be done to make sure the switching process is quick and reliable, especially between different broadband networks.
“Making network switching as simple as possible will not only help increase customer confidence but will also be crucial in ensuring consumers actually benefit from the government's goals of UK-wide gigabit broadband rollout.
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