Tax codes

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If you think your tax code is wrong

Usually, HM Revenue and Customs (HMRC) update your tax code using information they get from your employer or pension provider.

If your tax code is wrong, it’s usually because HMRC has incorrect or missing information.

To correct your tax code, check and update the details HMRC has about you.

Update your details

Using the online service is the quickest way to check and update your details.

  1. Sign in to the Check your Income Tax online service.

  2. Check your employment, pension, estimated taxable income, company benefit and expenses details.

  3. Update your details if there’s anything wrong or missing.

  4. Claim tax relief on your employment expenses - if you have any.

If you’ve left a job and did not get a P45 from your previous employer, ask them for one. This can help to update your details.

What happens next

If your tax code needs to change, HMRC will:

  • update your tax code
  • tell you and your employer the new tax code within 15 working days

After you’ve got your new tax code, if you’re paid: 

  •  monthly - it should be on your next or the following payslip
  •  weekly - it should be on your third payslip

If your payslip does not show your new tax code, speak to your employer to check they’ve got it.

If you’ve paid the wrong amount of tax, you can get a tax refund or pay the tax you owe.

If you cannot use the online service

If you think your tax code is wrong and you cannot use the online service, you can contact HMRC.

If you’ve started a new job, you should wait 35 days for HMRC to get your new income details before contacting them.

If you’re contacting HMRC on someone else’s behalf

If you want to help friends or family with their tax you can register as a ‘trusted helper’.

If you’re an agent and you need to tell HMRC about a change in your client’s income fill in a PAYE Coding Notice query form.

View a printable version of the whole guide

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