Tax codes, 2026/27
Emergency tax codes
From 6 April 2026 the emergency tax codes are 1257L W1, 1257L M1 and 1257L X. With one, tax is worked out on each payday on its own, which can mean paying too much until HMRC sends the right code.
W1, M1 or X at the end means an emergency code
An emergency tax code ends in W1 (week 1), M1 (month 1) or X, and some payroll software shows NONCUM instead. From 6 April 2026 HMRC's emergency tax codes are 1257L W1, 1257L M1 and 1257L X. Other codes can have the same endings, such as S875L M1 or C663L X.
| Ending | Used when |
|---|---|
| W1 | You're paid weekly, for example 1257L W1 |
| M1 | You're paid monthly, for example 1257L M1 |
| X | Your pay dates vary, for example 1257L X |
| NONCUM | Some payroll software shows this instead |
Each payday is taxed on its own
Codes are most often used on a cumulative basis, where your employer takes into account your pay and tax so far in the tax year. With an emergency code, tax is worked out on what you're paid in that week or month only, and you're taxed as if you were paid that amount every week or month of the year. On 1257L M1 each month gets about £1,048 of tax-free pay, whatever you earned earlier in the year. If you start a job part-way through the year after time without pay, that can mean paying too much tax until HMRC sends the right code.
When you might get one
- You start a new job and your employer does not have your previous income and tax details.
- You start getting company benefits or the State Pension. GOV.UK says you then keep the emergency code until the end of the tax year.
What to do
If you have a P45 from your previous job, give it to your new employer; if your previous employer did not give you one, ask them for it. If you started more than 35 days ago and think your code is still wrong, update your details with HMRC. If you paid too much, it is usually refunded through your pay once the new code is used.
Starting a new job
A new job without a P45 is one of the usual reasons for an emergency code. Giving your new employer your P45, or updating your details with HMRC, helps HMRC send the right code.
How to check or fix your tax code
- Find your code on your payslip, in a tax code letter from HMRC, or by signing in to HMRC's Check your Income Tax service or the HMRC app.
- If it looks wrong, use the same online service to check your jobs, pensions, estimated income and company benefits, and update anything that is wrong or missing. GOV.UK says this is the quickest way.
- If you have just started a new job, GOV.UK says to wait 35 days for HMRC to get your new income details before contacting them. If you left a job without a P45, ask your old employer for one.
- HMRC will tell you and your employer the new code within 15 working days. If you paid too much tax, your employer usually refunds it through your pay once the new code is used.
- If you cannot use the online service, contact HMRC about Income Tax.
Only HMRC can set or change your tax code. This page explains what codes mean; it is not personal tax advice. Sources: GOV.UK: If you think your tax code is wrong; GOV.UK: If you've paid too much or too little tax; GOV.UK: Tax codes.
Questions about emergency tax codes
What is the emergency tax code for 2026/27?
From 6 April 2026 the emergency tax codes are 1257L W1, 1257L M1 and 1257L X.
Do I pay more tax on an emergency tax code?
You can. Tax is worked out on each week or month on its own, so if you have had time without pay earlier in the tax year you may pay too much until HMRC sends the right code. Over a full year of steady pay the total is about the same.
How long does an emergency tax code last?
Usually until HMRC has your income details and sends your employer a new code. If you started getting company benefits or the State Pension, you keep the emergency code until the end of the tax year.
Other tax codes
- 1257LThe standard code: £12,570 tax-free.
- BRAll pay from this job taxed at 20%.
- D0All pay taxed at 40% (SD0: 21%).
- D1All pay taxed at 45% (SD1: 42%).
- 0TNo tax-free allowance on this job.
- NTNo tax taken from this income.
- K codesExtra taxable pay added, such as K475.
- Tax code checkerType your code to see what it means.
This page explains what emergency tax codes mean under GOV.UK and HMRC guidance for 2026/27. It is general information, not personal tax advice. Only HMRC can confirm or change your tax code. Tax figures are estimates for a full tax year at steady pay.
Sources
Rules checked 21 October 2026 against: GOV.UK: Emergency tax codes; HMRC: Rates and thresholds for employers 2026 to 2027; HMRC PAYE Manual PAYE11090: ways an employer can apply a tax code; GOV.UK: If you think your tax code is wrong; GOV.UK: If you've paid too much or too little tax. How we calculate.
Tax rates and thresholds are taken from HMRC, GOV.UK and Scottish Government publications. Contains public sector information licensed under the Open Government Licence v3.0.