Britain’s pensioners enjoyed a faster rate of growth in their disposable incomes last year than working-age adults after guaranteed state pension increases outstripped wage rises, according to official estimates.

The median disposable income for retired households increased by £300 (1.4%) after benefits, taxes and inflation were taken into account, in the year to April, while non-retired households experienced a 0.6% rise over the same period.

A jump in the number of retired people with occupational or private pensions, in addition to their state pensions, also played a large part in the persistently higher growth rate of retired household incomes.

The Office for National Statistics said that between 2008 and 2018 the median disposable income of retired households increased by £3,200 (16%), while non-retired household incomes grew by £900 (2.9%).

However, growing inequality among the UK’s 12.5 million over-65s meant many pensioners, especially those who rely on disability benefits, which have been sharply cut in recent years, were missing out.

While a measure of inequality covering all adults was relatively stable in recent years, the ONS said, inequality among people of pensionable age was heading back to levels last seen at the turn of the century.

Last month the Institute for Fiscal Studies said the trend for pensioner income growth to outstrip the growth rate of working households came to a halt last year, based on survey information from the Department for Work and Pensions.

Paul Johnson, the IFS director, wrote that 20 years of growing incomes had by 2012 pushed the level slightly higher than that of non-pensioners, once housing costs were accounted for. “But that upward trend seems to have halted,” he said.

The IFS study was based on DWP data drawn from a larger survey than the one used by the ONS. A spokesman for the IFS said the latest ONS survey, which covers a more recent period, relied more heavily on estimates of income levels.

Researchers at the ONS, who conceded the figures were part of a series of more experimental statistics, said its surveys nevertheless showed there was a “consistent growth in the incomes of retired households since 2008”.

They said a rise in the number of households reporting income from private pensions or annuities was a major factor, along with an increase in average income from the state pension, due in part to the effect of the “triple lock”, which guarantees a rise of 2.5% a year or the growth rate in earnings or inflation, if they are higher.

Average disposable income growth also halved to 1.2% in the year to April. The decline on the previous year was mainly because of slower wage growth, which primarily affected working households.

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Nathan Long, a senior analyst at the stockbroker Hargreaves Lansdown, said: “The higher rate of increase in pensioner incomes will do little to calm calls for greater fairness between the generations.

“Whilst incomes in retired households are increasing at a greater rate, non-retired households still have the greater income available after taxes as you’d expect. The income includes payouts from pensions, so whilst stagnating wages and generous state pension increases will be responsible in part, so too is the rush to access pensions that has happened since new, more flexible, pension rules were introduced.”

He added: “It is important to remember that the average ignores the fact there are many pensioners getting by on very low incomes.”

The ONS defines disposable income as the amount of money households have available for spending and saving after direct taxes, such as income tax and council tax, have been accounted for. It includes earnings from employment, private pensions and investments as well as cash benefits provided by the state.

