Emergency tax is a temporary tax code (e.g., 1257L followed by W1, M1, or X) applied when HMRC lacks your income details. It taxes you without considering previous pay or your full annual allowance.
Usually, on an emergency tax code, you end up paying more than you actually owe.
The good news? If you have overpaid tax, HMRC will usually refund the overpayment once your tax position is corrected.
Let us break down exactly what emergency tax is and why it happens.
What Is Emergency Tax?
Emergency tax is a temporary way of collecting Income Tax when HMRC does not yet have enough information about your earnings or tax position.
Basically, when you get paid, your employer or pension provider uses a tax code to deduct tax. That code is given to them by HMRC. That tax code tells your employer or pension provider how much of your income is tax-free and how the rest should be taxed.
The problem is that sometimes your employer simply does not have that code yet.
- Maybe you’ve picked up a second income.
- Maybe you didn’t hand over your P45 from your old job.
- Maybe you’re a pensioner taking your first withdrawal from a private pension.
Whatever the reason, HMRC steps in with a placeholder code. So that you are not left untaxed. That placeholder is what we call emergency tax.
Instead of delaying tax completely,
Why Do You Get Put on Emergency Tax?
You usually get put on emergency tax when your employer doesn’t have the information needed to apply your correct tax code.
The common reasons that might get you on an emergency tax include:
- You start a new job and don’t give your employer a P45 from your last one
- You didn’t complete HMRC’s Starter Checklist properly
- You’ve taken on a second job or a new pension alongside your existing income
- You’ve moved from self-employment into employment partway through the tax year
- You take your first taxable withdrawal from a pension pot
- Your circumstances changed. For example, you started getting a company car or other taxable benefit
How Does Emergency Tax Work?
Usually, HMRC’s PAYE system calculates your tax cumulatively. This means looking at everything you have earned and all the tax you have paid since April 6th.
For the 2026/27 tax year, the standard UK Personal Allowance remains at £12,570.
In a normal cumulative system, this annual tax-free safety net is divided smoothly across the year. This gives you a £1,048 tax-free allowance each month (or £242 a week). If you are unemployed for a few months, your unused tax-free allowances build up, and then it rolls over. As a result, it lowers your future tax bills.
But when you are put on an emergency tax code (like 1257L M1 or W1), the system operates completely on a non-cumulative basis.
Non-Cumulative tax completely ignores what happened in earlier months. So in case you start a job halfway through the year, it does not care that you were unemployed earlier. It only gives you one single month’s tax-free allowance (£1,048) and taxes the rest.
You may temporarily pay more tax than you ultimately owe because unused tax-free allowances from earlier in the tax year are ignored until your tax code is corrected.
Common Emergency Tax Codes in 2026/27
The most common emergency tax codes for 2026/27 are 1257L W1, 1257L M1, and 1257L X. Let’s look at them in detail:
1257L W1
This is one of the most common emergency tax codes.
The “1257L” part represents the standard Personal Allowance code used for many taxpayers.
The important part is W1.
It means a week 1 basis.
Instead of looking at your earnings since the start of the tax year, payroll only considers the current week’s pay.
Previous earnings are ignored. Yes, until HMRC issues your correct cumulative tax code.
1257L M1
This works in exactly the same way as 1257L W1.
The difference is that it’s calculated on a Month 1 basis instead of Week 1.
Each month’s salary is treated independently.
Your earlier earnings don’t affect the calculation.
1257L X
It is applied if your pay interval is irregular (e.g., fortnightly, four-weekly, or casual piecework).
Some payroll software systems automatically print “X” on your slip instead of writing out “W1” or “M1”.
Just like W1 and M1, it completely locks your tax calculation to that single pay packet. It prevents the system from balancing out your tax over the whole year.
Other Flat-Rate Emergency Codes
Beyond the 1257L variants, HMRC uses other flat-rate codes if your previous job history or income details are entirely missing.
- BR: This stands for Basic Rate. It taxes all income from this job at a flat 20%, and it gives you zero tax-free Personal Allowance. It is commonly used for second jobs where the Personal Allowance is already being used elsewhere.
- 0T: This code removes your Personal Allowance entirely. It taxes all of your earnings without giving any Personal Allowance, applying the normal tax bands from the first pound of taxable income. It can trigger 40% or 45% tax on larger paychecks.
- D0: This taxes all income from this specific source at a flat 40%. It is used for taxpayers in England, Wales, and Northern Ireland if HMRC thinks your total combined income exceeds £50,270.
- D1: This taxes all income from this source at a flat 45%. It is used if HMRC estimates your total annual income exceeds £125,140.
That said, the letters W1, M1 and X are often the biggest clue that you’re on emergency tax.
Why Am I Being Charged an Emergency Tax?
There are a few common reasons why an emergency tax might be applied:
- Starting a New Job: If you’re starting a new job and HMRC hasn’t given your new employer your tax details yet, you could be placed on emergency tax.
- Not Having a Tax Code: If HMRC doesn’t know your income or if they don’t have up-to-date information about you, you’ll be placed on emergency tax until they can sort things out.
- Multiple Jobs: If you have more than one job and your employers don’t know about each other, they might apply emergency tax because they can’t tell how much you’re earning from each job.
- Not Giving Correct Details: If you don’t provide your employer with your correct tax code or personal details, they might use emergency tax.
How Much Is Emergency Tax?
Emergency tax is not a fixed amount or a flat percentage rate. Instead, how much you pay depends entirely on how much you earn in that specific pay period. If HMRC already has the correct information but your employer has not yet received the updated tax code, the correction will normally be made automatically through PAYE.
If You’re Under the Standard Emergency Code (1257L M1 / W1)
Your payroll gives you exactly 1/12th of your tax-free allowance for that month (or 1/52nd for that week). Anything you earn above that fractional allowance is taxed through the standard bands:
- Gross monthly earnings from £0 to £1,048: 0% (Tax-Free Personal Allowance)
- Gross monthly earnings from £1,049 to £4,189: 20% (Basic Rate)
- Gross monthly earnings from £4,190 to £10,428: 40% (Higher Rate)
- Gross monthly earnings over £10,428: 45% (Additional Rate)
Note: If you live in Scotland, your payroll will only use Scottish tax rates if your emergency code starts with an ‘S’ (like S1257L M1). Without the ‘S’, your employer will temporarily use standard UK tax bands.
If You’re Under Other Temporary Codes
If your employer puts you on a basic flat-rate temporary code because they have zero info on your tax history, the deduction is a flat rate from your very first pound:
- BR Code: You pay a flat 20% on every single pound you earn.
- 0T Code: You get a 0% tax-free allowance. Your full income is progressively taxed at 20%, 40%, and 45% starting from your very first pound.
How To Get Off Emergency Tax?
For a new job, hand your P45 over as quickly as you can. Or fill in the Starter Checklist properly if you don’t have one. Once your employer submits this, HMRC can update your code within a couple of pay cycles.
For a pension withdrawal, check your Personal Tax Account online. You can see exactly what code HMRC has issued and whether it’s still on an emergency basis. If it is, you need to submit the relevant reclaim form rather than waiting it out. You will need form P55 for partial cash outs and form P53Z if you emptied the pot. You will need form P50Z if you have stopped working entirely.
Common Emergency Tax Scenarios
Let’s look at some common scenarios to better understand how much emergency tax you might end up paying.
1: Starting a New Job Without a P45
Imagine you’ve just started a new job, but you’ve either forgotten to give your new employer your P45 or you didn’t have it from your previous job. Your employer doesn’t have your full tax details, so they’ll apply an emergency tax code, which means they will likely tax you at the basic rate of 20%.
- You earn £1,500 per month
- Emergency tax is applied at 20%.
- Your tax would be £1,500 × 0.20 = £300 per month.
In this case, you’re paying the correct basic rate of 20%, but if your tax code was wrong or if you had multiple jobs, your employer might apply a higher rate temporarily.
2: Multiple Jobs and Emergency Tax
Let’s say you have two jobs, but your employers don’t know about each other. If they both don’t have the right information about your combined earnings, both might apply emergency tax. This can cause you to pay more tax than you should.
- Job 1: You earn £1,000 per month.
- Job 2: You earn £800 per month.
- Total income: £1,800 per month.
- Your tax code is applied to each job as an emergency, so you could be taxed at a higher rate (e.g., 40%) on the second job, or possibly even on both jobs.
In this case:
- Job 1: You’re taxed at the basic rate of 20%. Tax for Job 1 would be £1,000 × 0.20 = £200.
- Job 2: Because your second job might be taxed at a higher emergency rate (say, 40%), tax for Job 2 would be £800 × 0.40 = £320.
So, you’d end up paying a total of £200 + £320 = £520 in tax, even though you’re only earning £1,800 per month.
3. Special Emergency Tax Codes
In some cases, your emergency tax code might include specific letters or numbers that change the amount of tax you’re paying.
- M1 or W1: These codes are used when your employer applies emergency tax based on a month 1 or week 1 basis. This means that only your earnings from that particular month or week will be taxed, without considering previous months or weeks.
- Example: You earn £1,200 in a month with an M1 code, and your emergency tax code applies the basic rate of 20%. You’ll pay £240 in emergency tax for that month.
- BR (Basic Rate): If you’re taxed under the BR code, it means your entire income will be taxed at the basic rate (20%). This often happens if you’re on multiple jobs or if your second income is taxed separately.
- Example: If you earn £1,000 a month under the BR code, you’ll pay £200 in emergency tax.
What If You’re on a Higher Tax Band?
If you’re a higher-rate taxpayer and your tax code is wrong, you could find yourself paying emergency tax at a higher rate.
- Basic rate: If you’re under the basic tax code, you’ll pay 20% on your income.
- Higher rate: If you should be taxed at the higher rate of 40% and you’re on emergency tax, you’ll be taxed at this higher rate.
Example 3: Higher Rate Taxpayer on Emergency Tax
Imagine you should be taxed at the 40% rate because you earn more than £50,000 per year. But because you’re on emergency tax, you’re being taxed at the 40% rate on all your income until your tax details are updated.
- You earn £3,500 per month.
- You’re taxed at the higher rate of 40%.
- Tax: £3,500 × 0.40 = £1,400.
In this case, you’re paying £1,400 in tax, which could be a lot higher than what you should be paying under the correct tax code.
What Are The Deadlines For the Emergency Tax?
If you’re placed on emergency tax, here’s what you need to know about the key deadlines:
1. HMRC Tax Code Correction Deadline
HMRC aims to correct your tax code by the end of the tax year (April 5th). If you provide the correct tax information to your employer, they should update your code to avoid an emergency tax.
2. Tax Payment Deadlines
- PAYE Employees: Your employer will deduct tax each month. There are no additional deadlines unless you need to file a self-assessment.
- Self-Assessment: If you file a self-assessment, your tax return deadline is January 31st. Taxes owed must be paid by this date.
3. Claiming a Refund for Overpaid Emergency Tax
You can claim a refund for overpaid emergency tax within 4 years from the end of the tax year in which the overpayment occurred. For example, overpaid tax from 2021 can be claimed until April 5, 2025.
Impact of Emergency Tax on Your Pay
It’s important to know that being placed on emergency tax can leave you with a smaller paycheck than expected, especially if you’re taxed at a higher rate temporarily.
For example:
- You earn £2,000 in a month.
- If emergency tax applies at the basic rate of 20%, your tax will be £400.
- Your take-home pay would be £1,600.
However, if you were supposed to be taxed at the higher rate (40%), you might end up paying £800 in tax, and your take-home pay would drop to £1,200.
It’s a good idea to check your pay slips to make sure you’re not overpaying. If you notice that you’re being taxed too much, you can contact HMRC for a tax code correction.
How To Claim An Emergency Tax Refund?
Emergency tax rates are higher than the usual UK tax rates. When you have overpaid your taxes, you can claim your money back. After tax code correction, HMRC will inform you about your tax rebate if you have overpaid the tax. Here’s how to get it back.
Wait for a P800 Tax Calculation
HMRC will send you a P800 tax calculation at the end of the tax year. This will tell you whether you have paid more or less tax. You can get a refund online, provided you are entitled to it.
Contact HMRC Directly
You do not need to wait till the end of the tax year. You can get in touch with HMRC earlier by:
- Signing into your Personal Tax Account
- Making a call to HMRC using your National Insurance number, employer details, and income estimates.
Refund Timeline
After you have submitted a refund, it may take between 1 to 8 weeks to get the money back, depending on the method of claiming your refund and also depending on whether security checks are required or not.
Pension Emergency Tax
If your emergency tax is to do with the withdrawal of a pension, you might need to complete certain forms:
- P55: You have taken part of your pension, and you do not take regular payments.
- P50Z: You have taken out all your pension, and you are retired.
- P53Z: You have already taken out all your pension, and you are still working.
How To Avoid Emergency Tax?
While you can’t always avoid emergency tax, there are things you can do to make sure it doesn’t last longer than necessary:
- Update Your Tax Details: If you’ve recently changed jobs, make sure you provide your new employer with your full tax details, including your P45 or P60 from your previous job.
- Check Your Tax Code: Always check that your tax code is correct, especially when you start a new job or receive a new pay slip. Your tax code should match your personal circumstances.
- Contact HMRC: If you think you’re being taxed at the wrong rate or that your tax code is wrong, get in touch with HMRC to make sure everything is updated.
How Much Is Emergency Tax on Pensions?
When you make your first flexible pension withdrawal, your pension provider often has no cumulative PAYE history for you. As a result, the payment is frequently taxed using a Month 1 (M1) emergency basis. Most pension providers use an emergency Month 1 tax code because they have no previous PAYE information for that pension.
The system effectively assumes you’ll receive the same amount every month. Yes, for the rest of the tax year.
If you are someone making a single large withdrawal, that assumption can produce far more tax than you actually owe.
The Bottom Line
For most people, emergency tax is a temporary issue that can be corrected once HMRC has the right information.
The key is to check your tax code, understand why it has been applied and take action if it doesn’t look right.
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How CruseBurke Can Help
At CruseBurke, we regularly review PAYE records, tax codes and pension withdrawals to help clients understand whether they’re paying the correct amount of tax.
In many cases, a short review is enough to identify why emergency tax has been applied and whether any further action is needed.
If a refund is due, we can also guide you through the most appropriate route based on your circumstances, helping you avoid unnecessary delays.
Disclaimer: The general information provided in this blog about how much is emergency tax includes text and graphics. It does not intend to disregard any of the professional advice in the future as well.
