Billions of pounds worth of benefits go unclaimed each year, according to figures from the Department for Work and Pensions (DWP).
Pensioners are one of the largest groups failing to claim. Up to £2.8 billion in pension credit, a benefit used to top-up older people's weekly pension, was not taken up in tax year 2009/10.
When added to the other benefits pensioners are entitled to but failing to claim the amount of money not being utilised almost doubles to £5.5 billion.
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"There are still 1.8 million people in later life living in poverty. Claiming pension credit can make a huge difference to someone's income and quality of life," says Michelle Mitchell, charity director general of Age UK.
"The government needs to start an awareness programme, and move more towards a system where the DWP pays entitlements rather than an individual having to work their way through the benefits maze."
The figures on unclaimed benefits for 2009/10 include:
Up to 620,000 people failed to claim up to £2 billion in income support, and employment and support allowance
Up to 1.6 million people failed to claim up to £2.8 billion in pension credit
Up to 1.1 million people did not claim up to £3.1 billion in housing benefit
Up to 3.2 million people missed out on up to £2.4 billion in council tax benefit
Up to 610,000 people did not claim up to £1.95 billion in jobseeker's allowance
If you aren't sure you whether you are claiming all the benefits you are entitled to there are various agencies that will help you check. Websites such as turn2us.org.uk can quickly assess your benefit entitlement.
If you would prefer to speak to someone Turn2Us also has a confidential helpline on 0808 802 2000. Alternatively, you can visit your local Citizens Advice bureau.
You can also find out what benefits you can claim by using the ‘benefits adviser' questionnaire on the Directgov website.
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