Homeowners are paying £8.2 billion too much for insurance because they fail to shop around for the best deal, research has claimed.

Insurance broker rhinoinsurance said consumers who bought mortgage payment protection insurance, which pays their mortgage if they were unable to work, from the main High Street lenders were paying too much for the cover.

The group, which got ten people to pose as customers taking out the cover with the country's top ten mortgage lenders, said homeowners were being charged an average of £37.57 a month to cover mortgage repayments of £650.

But it claimed the same level of cover was available for just £25.68 a month if people went directly to an insurance broker, saving them £142.68 a year or £3,567 over the course of a 25-year mortgage.

According to the group, Cheltenham & Gloucester, part of the Lloyds TSB group, emerged as the most expensive place to get mortgage payment protection insurance, charging just over £50 a month to cover repayments of £650, followed by Abbey National at £39.26, and Barclays and Woolwich at £38.68.

But a spokeswoman from Cheltenham & Gloucester said rhinoinsurance were not comparing like with like.

She said: "The cover we offer consumers is very comprehensive. Not only do we cover the mortgage payments but we offer an additional cash payment of £3 for every £1,000 of the loan."

She said this meant someone with a £100,000 mortgage would receive £300 in cash each month if they lost their job or were unable to work.

Cover without this benefit would be much cheaper. Abbey National said its Paycare policy was more expensive because it offered cover against accident, sickness and unemployment.

The group said policies were cheaper if they only covered mortgage repayments if the holder was unable to work as a result of either unemployment or an accident or sickness.

It added that the policy kicked in after just 28 days of being off work.

Barclays and Woolwich, which are part of the same group, said their policy covered customers as soon as they could not work and also considered claims for depression and stress.

A spokeswoman from the Council of Mortgage Lenders said: "Clearly policies are different from each other. They have different levels of cover and different prices."