Why does the amount of income tax I pay change from month to month when my salary stays the same?

Income tax is payable on the taxable income earned in the tax year, which runs from 6 April to 5 April. The tax tables will round up to the nearest penny when calculating the amount of tax-free allowances that are applicable in each week or month.

As such, there may be minor fluctuations in the level of tax you pay. Of course, your tax-free allowances might change during the year, reflecting changes in your personal circumstances. This would result in changes to your tax code and your tax deductions.

Note: This content is provided as general background information and should not be taken as legal advice or financial advice for your particular situation. Make sure to get individual advice on your case from your union, a source on our free help page or an independent financial advisor before taking any action.