The study looked at the financial circumstances of the ‘Silent Generation’ – people aged 75+ who lived through the Second Word War – and challenges recent stereotypes of ‘wealthy pensioners’.

It said the average income of older (75+) pensioners is £59 a week less than younger pensioners and £112 a week less than working age adults.

An estimated 950,000 of older pensioners live below the current poverty threshold for a single pensioner, which is just £182 a week, the report said.

Janet Morrison, chief executive of Independent Age, said the findings show how misleading it is to treat all 11.8 million pensioners in this country as one group.

“It would be foolish to assume that inequality simply ceases to exist at retirement age, but that is exactly what some of the recent rhetoric around ‘intergenerational unfairness’ does.

“This is the ‘Keep Calm and Carry On’ generation that lived through the Second World War. The older people we spoke to as part of this research talked about ‘keeping a brave face’, ‘cutting their cloth’ and not wanting to ask for help. There is a real risk that this generation will be forgotten and left to suffer in silence.”

The report reveals that nearly three quarters of a million people aged 75+ – who will not benefit from the new State Pension which came into effect in April 2016 – have no income apart from the existing State Pension and other pensioner benefits.

But older pensioners are also less likely to claim Pension Credit, a benefit designed to boost the income of the poorest pensioners. An estimated three quarters of a million over 75s are entitled but are failing to claim, often unaware they qualify.

Independent Age is calling on the government to increase take-up of Pension Credit among older pensioners, private renters, women and single pensioners.