Darling and a case of fiscal drag?

According to the Budget 2010 Report, public sector current receipts in 2010-11 will be £541 billion. With expected public sector expenditure of £704 billion this leaves a deficit of £163 billion. Of these receipts, £146 billion or 27% is expected to come from income taxation. Several notable developments in the income tax system for 2010/11 include: the freezing of personal allowances, an income limit for personal allowances for those under 65, and the introduction of an additional income tax band.

Personal allowances are amounts of income that can be earned without being liable to income tax. This amount is to be frozen in 2010/11 at the level of 2009/10 so that for an individual under 65, this limit will remain at £6,475. Allowances are typically raised each year in accordance with the rate of price inflation. This then helps to reduce, in part, what is called fiscal drag. Fiscal drag occurs when there is an increase in the proportion of income taken in income tax as a result of allowances not being adjusted for inflation or for the rate of growth in earnings. In other words, by not increasing the amount of income exempt from taxation in 2010/11, any individual whose earnings rise will pay a higher proportion of their earnings in income taxation.

Another change in 2010-11 is the introduction of an income limit on personal allowances for those earning over £100,000. For every £1 earned above this limit, 50 pence will be taken from the allowance. Hence, given the allowance of £6,475 an individual earning £112,950 or more (i.e. £12,950 over the limit) will, in effect, no longer receive any personal allowance.

Now consider changes to the tax brackets. In 2009/10, an individual with an income tax liability of up to £37,400 (i.e. earnings of up to £43,875, once the personal allowance has been taken into account) pays income tax at 20%. This is the ‘basic rate’ band. With a liability of over £37,400, the excess (i.e. the amount over £37,400) is subject to tax at 40%. This is known as the ‘high rate band’. From the 1st April 2010, there is to be an ‘additional rate’ of 50%. The 50% rate will apply to taxable income over £150,000, while taxable income up to £37,400 will continue to be taxed at 20% and that between £37,401 and £150,000 will be taxed at 40%.

Now, an illustration of how the changes for 2010/11 will affect two individuals. Firstly, consider somebody on £110,000. Their tax allowance is ‘reduced’ by £5,000 to £1,475 and so they have a tax liability of £108,525. Of this, they will pay £7,480 at the basic rate (20% of £37,400) and £28,450 at the higher rate (40% of £71,125). With a tax bill of £35,930, their average rate of income tax in 2010-11 will be 32.66%. In 2009/10, the total tax bill will have been £33,930 (20% of £37,400 plus 40% of £66,125) and so an average rate of tax 30.85%

Finally, consider an individual on £200,000. Their income tax bill in 2010/11 will be £77,520 (20% of £37,400 plus 40% of £112,600 plus 50% of £50,000) and so they will face an average rate of tax income tax of 38.76%. In 2009/10 the tax bill would have been £69,930 (20% of £37,400 plus 40% of`£156,125), an average rate of income tax of 34.97%


The £20 billion tax raid about to hit The Times, Lauren Thompson (27/3/10)
How to beat the new 50% top rate of tax The Times , Mark Atherton (27/3/10)
Budget 2010: Darling draws election battle lines BBC News (24/3/10)
High earners will feel like they have taken a pummelling The Scotsman, Jeff Salway (27/3/10)

Further information
For the full Budget Report, see Budget 2010: Complete Report HM Treasury, March 2010
(The above consists of the two elements, Economic and Fiscal Strategy Report and Financial Statement and Budget Report. It’s a fairly large pdf file and may take a few seconds to download.)
For the particular measures and their impact on government expenditure and/or revenue, see Annex A: Budget policy decisions of the Financial Statement and Budget Report.
See also Rates and allowances – Income taxation HM Revenue and Customs
(Note: from here you can also link to other tax rates.)


  1. Consider the efficiency and equity arguments for and against the income tax changes in 2010/11.
  2. What do you understand by the terms the marginal rate of tax and the average rate of tax?
  3. How will the changes to the income tax system in 2010/11 affect the marginal and average income tax rates? You could perhaps try plotting these in a chart for different gross incomes.
  4. How can fiscal drag occur even if personal allowances are raised by the rate of inflation?