By Tax Calculator UK · Published · 8 min read
What is an emergency tax code?
An emergency tax code is a temporary code your employer uses when HMRC hasn't yet sent the right one for you. It usually appears when you start a new job without a P45, start a second job, begin a pension, or when your circumstances change mid-year.
For 2026/27 the emergency code is normally 1257L with W1, M1 or X after it. Some employers will instead use BR or 0T depending on what you tell them on the starter checklist. None of these change how much tax you owe for the year. They change how much is taken from each payslip until HMRC catches up.
W1, M1 and X: the non-cumulative codes
Normally PAYE is cumulative. Each payslip looks at your pay and allowance for the year so far, so if you start in October you get the unused allowance from April to September straight away. W1 (weekly), M1 (monthly) and X switch that off.
On 1257L M1 you get one month of allowance, £1,047.50, every month regardless of what happened earlier in the year. If you weren't working before, that means you pay more tax than needed until your code is corrected. The overpayment normally comes back through payroll once HMRC issues a cumulative code.
Tax code BR
BR means basic rate. All the pay from that job is taxed at 20% (or the Scottish equivalent with SBR), with no tax-free allowance. It is the usual code for a second job or a second pension, because your allowance is already used on your main income.
BR is right if your other income uses the full £12,570 allowance. If your main job pays less than that, some allowance is going to waste and you can ask HMRC to split it between jobs. Our guide to tax on a second job explains how, and the full tax code BR explainer covers what the code costs and how to challenge it.
Tax code 0T
0T means no tax-free allowance at all. Unlike BR, pay is taxed through the normal bands: 20%, then 40% and 45% as it rises. It is used when HMRC has no information about you, when you haven't given your employer a P45 or starter checklist, or when your allowance has been fully withdrawn because you earn over £125,140.
0T does not by itself prove an overpayment. Your allowance may already be used by another job, pension or tax-code adjustment. Check the reason in your HMRC online account before asking for a change.
D0, D1 and K codes
D0 taxes all pay from that source at the higher rate (40%) and D1 at the additional rate (45%). They are used for a second job when your main income already reaches the higher or additional rate band.
A K code is the opposite of an allowance: the number shows extra income to add to your pay before tax. It is used when you have taxable benefits, such as a company car, or tax owed from an earlier year that is bigger than your allowance. K475, for example, removes your allowance and adds about £4,750 to your taxable pay. HMRC caps the tax taken under a K code at half of each payslip.
How each code changes the tax on £30,000
Income Tax only on £30,000 a year in England, Wales or Northern Ireland, assuming the code applies for the whole year. National Insurance is the same whichever code you are on.
| Code | How pay is taxed | Income Tax for the year |
|---|---|---|
| 1257L | £12,570 tax-free, then 20% | £3,486 |
| BR | All at 20% | £6,000 |
| 0T | No allowance, normal bands | £6,000 |
| D0 | All at 40% | £12,000 |
How to get off an emergency tax code
Once HMRC sends the right code, any tax you overpaid in the current year is usually refunded in your next payslip. If you have left the job, HMRC will normally refund it after the tax year ends. To see what your pay should look like on any code, use the tax code calculator.
- Give your new employer your P45 from your last job. See what a P45 is.
- If you don't have one, fill in the starter checklist your employer gives you.
- Check and update your details in your HMRC online account or the HMRC app.
- Contact HMRC if the code is still wrong after a couple of pay periods.
Record the full code, not just its number
A prefix or period marker can change how a deduction is interpreted. Keep the code exactly as shown and the payslip date when comparing it with a notice or an annual estimate.
Frequently asked questions
What is the emergency tax code for 2026/27?
Usually 1257L W1, 1257L M1 or 1257L X. These give you one pay period of allowance at a time instead of looking at the whole tax year.
Check it on GOV.UK: Tax codes (opens GOV.UK in a new tab)
Is 1257L an emergency tax code?
Not on its own. 1257L is the standard code for 2026/27. It only works as an emergency code when W1, M1 or X follows it.
Check it on GOV.UK: Tax codes (opens GOV.UK in a new tab)
How long does an emergency tax code last?
Usually until HMRC sends your employer the right code. GOV.UK says it can take up to 35 days after starting a job for HMRC to update your code, so expect one or two payslips on it.
Check it on GOV.UK: Tax codes (opens GOV.UK in a new tab)
Is BR an emergency tax code?
Not strictly. BR is the normal code for a second job, but employers sometimes use it as a stopgap when they have no information about you.
Check it on GOV.UK: Tax codes (opens GOV.UK in a new tab)
Do I get emergency tax back?
Yes. Once HMRC sends your correct code, overpaid tax is normally refunded through payroll. If you've stopped working, HMRC refunds it after the tax year ends.
Check it on GOV.UK: Income Tax rates and allowances (opens GOV.UK in a new tab) · National Insurance rates and category letters (opens GOV.UK in a new tab)
What is the difference between BR and 0T?
Both give no tax-free allowance. BR taxes everything at 20%, while 0T uses the normal bands, so higher earners pay 40% or 45% on part of their pay.
Check it on GOV.UK: Tax codes (opens GOV.UK in a new tab)
Why is my tax code K?
A K code means you have income or benefits to tax that exceed your allowance, such as a company car or tax owed from a previous year.
Check it on GOV.UK: Tax codes (opens GOV.UK in a new tab)