What Is Emergency Tax? How to Fix It and Get a Refund
An emergency tax code is a temporary code used when your employer does not have your details. It can make you overpay for a while.
What an emergency tax code is
If your employer or pension provider does not have enough information about you, they use a temporary code. These end in W1, M1 or X, for example 1257L W1. The suffix means tax is worked out on each payment on its own, without adding up your pay across the year, so you can overpay at first.
Common reasons for it
- You start a new job without a P45.
- You take a first pension withdrawal and the provider has no tax code for you.
- You start a second job or receive a pension.
How to fix it
- Give your employer your P45, or complete the starter checklist with correct details.
- Check your code in your personal tax account.
- Tell HMRC if the code looks wrong. They send your employer the right one, and any extra tax is usually refunded in your pay.
You can check what a code means with our tax code checker. If you paid too much, see how to claim a tax refund.
This guide is general information, not financial or legal advice. Rates checked 8 October 2026 against GOV.UK.
Frequently asked questions
What does an emergency tax code look like?
It is the normal code followed by W1, M1 or X, such as 1257L W1.
Will I get the extra tax back?
Yes. Once your employer has the right code, any overpaid tax is normally refunded through your pay or by HMRC.
How long does emergency tax last?
Until your employer receives your correct tax code from HMRC, which is often within a month or two.
Related
- What Is a Tax Code? 1257L and Other Codes Explained
- What Is a P45 and What Do You Do With It?
- How to Claim a Tax Refund in the UK
Figures are for the 2026/27 tax year from official sources and are estimates for guidance only, not financial or legal advice. Printed from ukanswers.co.uk.