Britons are throwing away billions of pounds on unnecessary insurance policies, a leading consumer group has claimed.

Uswitch Personal Finance says that £28.5 billion is wasted on additional mobile phone cover, life insurance, critical-illness cover, mortgage protection and payment insurance policies.

Many people fork out for extra mobile phone insurance when they are often covered under travel, personal possessions or all-risk home contents insurance. Although the policy would not pay out for fraudulent calls made on a stolen mobile, many phone insurers would not cover this anyway.

Experts say life insurance is only necessary for homeowners, those in debt or those with families who are dependent on a regular income. But company pensions often offer death-in-service benefits as part of the package.

Mortgage protection will cover policyholders who lose their jobs or find themselves unable to work due to sickness, but most will only pay out for a year and many companies offer their staff sick pay which would otherwise cover them.

The Financial Ombudsman Service receives over 1,000 complaints a year from people who are self-employed but have found out only when they try to make a claim that they do not qualify for the expected payment.

Critical illness cover offers a lump sum if policyholders are diagnosed with a serious illness but experts say it is better value to combine life and critical illness policies.

Payment protection insurance can be bought for much less through an insurance company than a bank but policyholders with savings are usually able to meet the cost of their repayments without undue financial stress.

Andy Smith, product manager at Uswitch Personal Finance, said: "It is crucial people have the right insurance and that they don’t end up paying more to insure items twice."