It's an astonishing figure that makes you wonder why so many Australians are struggling for every cent.

To find out if some of it is yours, all you have to do is know how to ask.

Carer Donna Letchford has discovered that the old saying 'if you don't ask you don't get' could be a perfect motto for Centrelink.

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Letchford had no idea she was entitled to hidden handouts worth $114 a fortnight as a carer for a child with learning difficulties. She didn't ask, and Centrelink certainly didn't tell her.

"People don't know, so they don't ask. It all becomes too hard for them to look up services on the internet or in literature, so they don't end up getting anything," she said.

"A little while ago I had a family member that I needed to care for a little bit extra. I was still able to work but it did take up more time and I didn't realise I was eligible for Carers' allowance until I looked into it a bit more."

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No Letchford helps others find missing entitlements through the community support group Camcare.

And as Australia's most influential independent think tank The Australia Institute has discovered, she's certainly not the only who's missed out on payments.

The Australia Institute used the Government's own figures to find out exactly how many Australians are missing out, and found that over a million people aren't being paid the benefits they're entitled to.

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All the emphasis is on catching the cheats, but in fact more Australians are missing out than the total number that are ripping off the system.

According to The Australia Institute's research fellow David Barker, author of the report 'Missing Out' "the Government has already decided these people deserve the money. They should be doing something to make it easier for them to receive it."

He discovered that Centrelink forms are too complicated, meaning people are bamboozled into not making claims.

• The Australia Institute - www.tai.org.au
• Camcare - www.camcare.org.au
• Centrelink - www.humanservices.gov.au

This reporter is on Twitter at @RichoTT7