Three in 10 people aged 66 and over rely on social protection for 90 per cent of their income, a report has shown.
A new Age Action report shows many can't cover new costs linked with older age, in health, transport and housing, which is causing distress.
A fifth of older couples and two fifths of older people living alone could not cope with a once-off expense of over €1,200.
Age Action policy specialist Nat O'Connor said many are at risk of poverty.
"Well we know that poverty is a significant problem for older people, at the moment one in three people living alone is at poverty, and we also know there is a large number of people suffering deprivation, which means they can't afford the basic items," he told Newstalk radio.
"That's certainly a concern, particularly at the moment with the higher cost of living.
Mr O'Connor also highlighted the pension gaps between men and women, leaving women more vulnerable to poverty.
"The ERSI reckons there is a 35 per cent pension gap between men and women, which is to say women's pensions are a third lower than mens on average, so that is a huge gap.
"We also know that in situations where there is a bereavement, a women is left as a widow, and can lose an awful lot of pension income, and at the same time, as all the same incomes at the same house."
