One in five taxpayers will be dragged into higher tax rates by 2027 – sparking new Conservative Party demands for emergency cuts.
Nearly eight million people are forecast to pay 40% or more due to the freezing thresholds.
That will include some teachers, nurses and electricians.
Tory MPs last night said it was time for Prime Minister Jeremy Hunt to speed up tax cuts.
Former Cabinet Secretary John Redwood said: “Taxes are so high that people don’t work harder and get promoted with longer hours and more responsibility.”
Tory MP David Jones said: “The Government is using fiscal drag as a means to increase revenue – a tactic Labor has long been in but the Conservatives were not expecting.”
Experts say it represents a “seismic shift” with the proportion of adults climbing to the higher group quadrupling since the early 1990s.
Nearly two million more people will have to pay higher tax rates, up to £50,271, between now and 2027-2028 due to a six-year freeze on income tax thresholds that started last April.
The pain of workers is compounded when incomes do not keep pace with inflation – at 10.1%.
“Higher tax rates have shifted from something reserved for the richest people to something a much larger proportion of adults are likely to experience,” said Isaac Delestre, of the Institute for Fiscal Studies.
A Treasury spokesman said “difficult decisions” must be made to fix public finances after Covid and the invasion of Ukraine.