Dementia patients in the UK face a "care tax" because they are left to sort out much of the care they need themselves, experts say.
The Alzheimer's Society found that on average, the equivalent of £32,242 a year was spent on care per patient.
But the researchers said on average only a third - £10,784 - came from NHS or council funds, leaving a shortfall.
The charity said it was unfair as those with cancer or heart problems got their care free on the NHS.
The research - carried out by the London School of Economics and Kings College London - was carried out to update figures compiled by the charity in 2007.