Emergency tax codes
If your tax code ends in ‘W1’ or ‘M1’ or ‘X’ you’re on an emergency tax code. For example:
- 1257L WI
- 1257L MI
- 1257L X
You may be put on an emergency tax code if HMRC does not get your income details in time after a change in circumstances such as:
- a new job
- working for an employer after being self-employed
- getting company benefits or the State Pension
Emergency tax codes are temporary. HMRC will usually update your tax code when you or your employer give them your correct details. If your change in circumstances means you have not paid the right amount of tax, you’ll stay on the emergency tax code until you’ve paid the correct tax for the year.
Updating your details
Your employer can help you update your tax code by sending details about your previous income or pension to HMRC.
If you’ve started a new job
Give your employer your P45 from your previous job. If you do not have a P45, your employer should ask you for the information they need instead.
If you’ve started working for an employer after being self-employed
Your employer should give you a ‘starter checklist’ - this is a form you can use to give them details about your previous employment.
If you’ve started getting company benefits or the State Pension
The emergency tax code will stay in place until the end of the tax year. This means you’ll pay the right amount of tax for the current tax year. In the new tax year HMRC will put you on a regular tax code.