Tax cuts or tax rises? The issue of fiscal drag

The UK Chancellor of the Exchequer, Jeremy Hunt, delivered his Spring Budget on 6 March 2024. In his speech, he announced a cut in national insurance (NI): a tax paid by workers on employment or self-employment income. The main rate of NI for employed workers will be cut from 10% to 8% from 6 April 2024. This follows a cut this January from 12% to 10%. The rate for the self-employed will be cut from 9% to 6% from 6 April. These will be the new marginal rates from the NI-free threshold of £12 750 to the higher threshold of £50 270 (above which the marginal rate is 2% and remains unchanged). Unlike income tax, NI applies only to income from work (employment or self-employment) and does not include pension incomes, rent, interest and dividends.

The cuts will make all employed and self-employed people earning more than £12 750 better off than they would have been without them. For employees on average incomes of £35 000, the two cuts will be worth £900 per year.

But will people end up paying less direct tax (income tax and NI) overall than in previous years? The answer is no because of the issue of fiscal drag (see the blog, Inflation and fiscal drag). Fiscal drag refers to the dampening effect on aggregate demand when higher incomes lead to a higher proportion being paid in tax. It occurs when there is a faster growth in incomes than in tax thresholds. This means that (a) the tax-free allowance accounts for a smaller proportion of people’s incomes and (b) a higher proportion of many people’s incomes will be paid at the higher income tax rate. Fiscal drag is especially acute when thresholds are frozen, when inflation is rapid and when real incomes rise rapidly.

Tax thresholds have been frozen since 2021 and the government plans to keep them frozen until 2028. This is illustrated in the following table.

According to the Institute for Fiscal Studies, the net effect of fiscal drag means that for every £1 given back to employed and self-employed workers by the NI cuts, £1.30 will have been taken away as a result of freezing thresholds between 2021 and 2024. This will rise to £1.90 in 2027/28.

Tax revenues are still set to rise as a percentage of GDP. This is illustrated in the chart. Tax revenues were 33.2% of GDP in 2010/11. By 2022/23 the figure had risen to 36.3%. With neither of the two changes to NI (January 2024 and April 2024), the OBR forecasts that the figure would rise to 37.7% by 2028/29 – the top dashed line in the chart. After the first cut, announced in November, it forecasts a smaller rise to 37.3% – the middle dashed line. After the second cut, announced in the Spring Budget, the OBR cut the forecast figure to 37.1% – the bottom dashed line. (Click here for a PowerPoint of the chart.)

As you can see from the chart, despite the cut in NI rates, the fiscal drag from freezing thresholds means that tax revenue as a percentage of GDP is still set to rise.


Information, data and analysis


  1. Would fiscal drag occur with frozen nominal tax bands if there were zero real growth in incomes? Explain.
  2. Find out what happened to other taxes, benefits, reliefs and incentives in the 2024 Spring Budget. Assess their macroeconomic effect.
  3. If the government decides that it wishes to increase tax revenues as a proportion of GDP (for example, to fund increased government expenditure on infrastructure and socially desirable projects and benefits), examine the arguments for increasing personal allowances and tax bands in line with inflation but raising the rates of income tax in order to raise sufficient revenue?
  4. Distinguish between market-orientated and interventionist supply-side policies? Why do political parties differ in their approaches to supply-side policy?
  5. What is the Conservative government’s fiscal rule? Is the Spring Budget 2024 consistent with this rule?
  6. What policies were announced in the Spring Budget 2024 to increase productivity? Why is it difficult to estimate the financial outcome of such policies?