In the last tax year, £107.97 billion was spent on pensions and £26.57 billion on housing benefits.
It means that 41.9% of Britain's total social security budget is allocated to pensions, compared with 10.3% on housing benefits, according to analysis by the Press Association.
To put this in context, £1 in every £7 the Government currently spends goes towards pensions, up from £1 in £8 in 2010/11. This is more than the amount spent on all education services, which is currently £1 in every £9.
In response to the findings, critics accused the Government of "making older people better off at the expense of youngsters". However, it has defended the spending, claiming pensioners "deserved to be looked after".
Should the current rate of pension spending increases continue, half of the entire welfare budget could go towards paying for pensions by the financial year 2022/23.
And with the latest population projections suggesting the number of people of pensionable age in the UK is likely to rise from 19.2% to 21.8% by 2037, government spending on pensions is likely to climb still further.
Another factor likely to drive up spend is the "triple lock" on pensions, which was introduced by the coalition in 2010 and guarantees the state pension will rise every year by the higher of inflation, average earnings or a minimum of 2.5%.
When asked about the spending figures, a spokesman for the Department for Work and Pensions told the Press Association: "Older people who have worked hard all their lives, and contributed to our society and economy over many decades, deserve to be looked after in their retirement.
"The Government is determined to ensure financial security for working people at every stage of their lives, including in old age. This is why we have protected the incomes of millions of pensioners with the triple lock and committed to continuing this uprating mechanism for the state pension until 2020."
However, TaxPayers' Alliance chief executive Jonathan Isaby criticised the Government and said spending plans needed to "match economic reality".
He said: "The bills for pensions are enormous and they will only continue to spiral ever upwards because of our ageing population and the deliberate decision to protect them from the savings being made elsewhere in government.
"We are making older people better off at the expense of young workers and that cannot be right. Nobody wants to see pensioners living on the breadline but we must make sensible and rational decisions on pensions that match economic reality."