The Association of British Insurers dismissed the criticism, citing an enormous increase in claims that could not have been foreseen.
Which? points out that insurers blame burglary claims, which have doubled since 1987, and claims for subsidence damage, up from pounds 90m to pounds 540m over the same period.
'Insurers have raised premiums because they expect similar levels of claims this year. But some companies are hiking your premiums to recoup losses made in previous years, when they underestimated the level of claims,' the magazine says. 'In other words, you're being made to pay for their mistakes. There is a real danger some people will no longer be able to afford insurance.'
Which? says that under the Zurich home buildings policy pounds 50,000 of buildings cover in a high-risk area has risen 132 per cent in the last 12 months, 124 per cent under Municipal Mutual's home and contents policy and 116 per cent under the Jardines homesure scheme.
Among the biggest increases in contents policies was a 95 per cent rise for cover in a typical high-risk area under the Eagle Star direct homechoice policy. Cover in a typical low-risk area under this policy rose 92 per cent. Norwich Union's contents plus policy raised premiums for cover in a low-risk area by 93 per cent and 50 per cent for a high-risk area.
Clive Longhurst, a spokesman for the Association of British Insurers, said: 'No one could have foreseen the level of losses we have had in the last few years.
'The cost of theft claims increased 62 per cent between 1990 and 1991. You would expect it to rise by inflation, plus a bit extra because of the recession, but 62 per cent was over the top. This is one of the factors which the insurance companies had no control over and which have messed up the sums.'
Which? is also critical of endowment policies and other forms of life insurance which mix basic life cover with investment. Many such policies are used to repay mortgages but others are used as a form of regular saving.
Using figures from the Securities and Investments Board, the chief regulator of investment business, the Consumers' Association estimated that 18 per cent of people who purchase investment- linked life policies surrender them within the first 12 months of the policy's term. Policyholders are not normally entitled to any return on their investment in the first 12 months and the Consumers' Association says figures from the Association of British Insurers show that the early leavers during 1990 could have lost pounds 165m.Reuse content