Tax calculations

Tax codes explained

  • How to check that your tax code is correct
  • Tips on understanding your coding notice
  • When to notify HMRC of changes and errors
  • Where to find out more about tax codes
  • What to do if you're on an emergency tax code

What's in this guide

Your tax code

We explain what the numbers and letters in your tax code mean

Your coding notice

What the coding notice HM Revenue and Customs sends you can tell you

Checking your tax code

What to do if your tax code is wrong. How to notify HMRC if you're on the wrong tax code

Emergency tax codes

What to do if you’re on an emergency tax code 

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