This article was originally published on the BBC website on 21 September 2015.  Click here to read it in full.

What is housing benefit?

It's a means-tested benefit paid to people on low incomes. For tenants in council or housing association properties it will usually cover their whole rent if they have no other income. For many of those in the private sector it will not pay the whole rent even if they have no other income. Housing benefit is withdrawn as income rises, but an increasing number of people in work claim at least some housing benefit.

How expensive is it?

Very. At over £25 billion it is one of the biggest and fastest-growing parts of the welfare bill.

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