British Gas stands accused of ripping off customers who pay for boiler insurance.
One in six are paying more than £500 a year for cover – with some forking out £750 or more.
Watchdog Which? found it to be the dearest among companies that offer attractive introductory deals only to ramp up premiums for two-thirds of their customers.
On average, British Gas customers pay from £354 to £375 for an annual service and boiler maintenance. But 17 per cent pay more than £500 a year.
British Gas dominates the boiler cover market, says the watchdog.
Three in five Which? members who have the insurance are with the energy giant.
Which? magazine editor Harry Rose said: “The eye-watering premiums charged by British Gas seem impossible to justify.
“Many new boilers come with a warranty up to 10 years, so it is worth checking before you consider separate boiler
insurance.”
Homeserve charges the next highest premiums, averaging £288 to £344. Corgi is cheapest, from £242 to £277.
Modern boilers typically cost from £1,000 to £2,000 – with replacement covered by
maintenance insurance.
British Gas said: “The figures in this survey are not representative of our actual customer base.
The average premium for our HomeCare customers is £258 and for those with an £60 excess on their policy this figure is lower at £186.
“Some customers choose a more comprehensive policy with us, also covering drains, plumbing and electrical appliances.”
