By bizn_fun 
Governments have historically raised tax thresholds in line with inflation, to try to ensure your take-home pay keeps up with the cost of living.
Weekly earnings across Britain grew at an annual rate of 0.8% between October and December after accounting for inflation, the latest Office for National Statistics (ONS) data shows.
That means growth in average salaries has now consistently beaten the pace of price rises since July 2023.
But thresholds have been frozen for the whole of that period and will remain stuck into the next decade.
According to our calculations, the freeze in thresholds will add £465 to the 2030-31 income tax and National Insurance bill for someone currently earning £39,000, which is the salary of the average UK worker.
Of that, £227 would be due to the extended freeze announced by the current Chancellor Rachel Reeves in November.
Someone on £50,000 would pay an estimated £1,309 more, of which £704 would be because of the extension from 2028-29.
You can read more about how the calculator works in the final section of this article.
Freezing thresholds is often called a stealth tax by economists because it increases the tax take without a government having to put up rates.
Both Labour and Conservative governments have used it to raise additional revenue. Extra money from tax receipts helps pay for public services such as the NHS, schools and welfare spending.
Most earners will pay more because of the freeze. But people whose pay rises move them across the thresholds into the basic and higher rates are likely to see the biggest jumps in what they owe.
The government published its own analysis of a range of its tax and spending decisions since late-2024, including frozen tax thresholds. This found the lowest income households benefit, and the highest lose out, external.
But this only goes up to 2028-29, so does not include the period covered by the extended freeze.
Analysis by the National Institute of Economic and Social Research (Niesr) shows lower and middle-income households are worst hit by the extension to the freeze, in percentage terms, external.
Thresholds were initially frozen in 2022 by former Conservative Chancellor Rishi Sunak, who paused them until 2026.
The Conservatives later extended that for a further two years, before Reeves announced she would keep it in place until 2031.
By 2030-31, official forecaster the Office for Budget Responsibility (OBR) estimates an additional 5.2 million people will be paying the basic rate of income tax because of threshold freezes first introduced in 2022-23.
An estimated 4.8 million more will be paying the higher rate, and 600,000 more the additional rate.
It forecasts that the freezes to income tax thresholds will generate £56bn in revenue in 2030-31. Of that, £12bn will be down to Reeves’s extension.
Additional reporting by Lucy Dady and Jess Carr