Emergency tax codes

You’re on an emergency tax code if your tax code ends in:

  • W1 - used when you’re paid weekly, for example 1257L W1
  • M1 - used when you’re paid monthly, for example S875L M1
  • X - used when your pay dates vary, for example C663L X

You could also see ‘NONCUM’ on your payslip, depending on your employer’s payroll software.

If your tax code does not end in W1, M1, X or NONCUM, you’re not on an emergency tax code. You can check what your tax code means.

What an emergency tax code means

Usually, your tax is worked out based on your total income so far in that tax year.

If you’re on an emergency tax code your tax is worked out based on what you’re paid in that week or month only. You get taxed as if you’re paid that amount every week or month of the year.

This could mean you pay the wrong amount of tax.

If you’ve started a new job 

When you’re paid for the first time, your new employer tells HM Revenue and Customs (HMRC) that you’ve started working for them. 

If your new employer does not have your previous income and tax details, you’ll be paid using an emergency tax code. This is usually temporary.

If you’ve got a P45 from your previous job, give it to your new employer. This gives them your details and can help take you off the emergency tax code. If your previous employer did not give you a P45, ask them for one.

HMRC will usually update your tax code when they get all your details from your new and previous employers. They’ll send the tax code to you and your new employer. This can take up to 35 days from when you start your job. 

If you have not paid enough tax, you’ll stay on the emergency tax code until you’ve paid the correct tax for the year.

If you’ve paid too much tax, you can get a tax refund

If you started a job more than 35 days ago

If you think your tax code is still wrong, find out how to update your tax code

If you’ve started getting company benefits or the State Pension 

You might be put on an emergency tax code if you start getting company benefits or the State Pension. This is normal and helps you pay the right amount of tax for that tax year.

Check your tax code online to make sure it includes the company benefit or State Pension. If they’re not included, update your details in the tax code online service or by contacting HMRC

You’ll have an emergency tax code until the end of the tax year. In the new tax year, you’ll be put on a non-emergency tax code.