A think tank has called for greater investment in local authorities to tackle regional inequality.
Disposable income is the amount of money people have available for spending or saving after taxes and social contributions, and is used by economists as a way of comparing the economic welfare of different areas.
The Office for National Statistics estimates Powys residents each had around £19,772 in disposable income as of 2022.
The figures show disposable incomes have on average grown by 3.2% a year in the area since 1997, the second highest rate in Wales.
However, this was still close to the UK rate of 3.1%.
The ONS suggests disposable income may have taken a hit from recent price rises, although data is not available for the impact of inflation at a local level.
In Powys, disposable incomes grew by 3.5% between 2021 and 2022, below the CPIH inflation rate of 7.9%.
Benedikt Stranak, researcher at the New Economics Foundation think tank, says inflation has "made us poorer".
"Despite promises of ‘levelling up’, year after year we see the same old pattern – disproportionate public investment in London, and very little in other parts of the country," he said.
Mr Stranak continued: "The damage caused is immense. More people are being forced to rely on foodbanks, and the lack of economic security is fostering a climate where racism and hatred can thrive, as evidenced by recent far-right riots.
"However, simply more growth isn’t the solution. In 2022, six out of the 10 local areas with the highest GDHI per capita were in inner London, which also has the highest poverty rate of all UK regions."
The NEF is calling for the Government to "empower and properly fund local authorities" to help with the cost-of-living crisis and reinvigorate local economies.
A Treasury spokesperson said: "We inherited an economy that has barely grown these past 14 years which has impacted people’s living standards.
"The only way to achieve sustainable growth is by fixing the foundations so we can rebuild this country and deliver a Britain that is better off."