We have previously published a thorough guide on tax codes but a quick summary is that a tax code is used to adjust how tax is calculated on an income source. It works by adjusting the personal allowance in order to take more or less amounts in tax. Some codes even restrict which bands of tax are used.
Below is our tax code decoder, which allows you to enter in any tax code and it will show you what the tax code means as well as the personal allowance indicated by the code. Give it a try!
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