Analysis by the Centre for Policy Studies (CPS) indicates that a worker currently earning £50,000 will be £505 worse off in real terms by 2030-31 due to this policy.
Conversely, pensioners are projected to be at least £306 better off, and those on standard universal credit £290 better off, thanks to the 'triple lock' and benefit increases.
The CPS described this as 'fiscal drag in action', quietly increasing taxes for millions of workers while protecting state pension and benefit recipients.
A Treasury spokesperson defended the measures as 'fair and necessary', while Ms Reeves had said the tax freezes were needed to fund public services, cut debt, and address the cost of living while announcing the Budget.