29/10/2026
PAYROLL UNPACKED | WEEK 7 OF 12
“EMERGENCY TAX”: WHAT DOES IT ACTUALLY MEAN?
Have you ever started a new job, received your first payslip and wondered why HMRC appears to have taken more tax than you expected?
You might have been told you're on “emergency tax”.
But what does that actually mean, and are you really paying a higher rate of Income Tax?
FIRST, LET'S CLEAR UP A COMMON MISUNDERSTANDING.
Emergency tax isn't a separate tax, and it doesn't automatically mean you're being charged a higher tax rate.
It generally means your Income Tax is being calculated on a temporary, non-cumulative basis because your full tax information isn't yet being taken into account.
This often happens when you start a new job and your employer doesn't have all the information about your previous earnings and tax deductions.
HOW CAN YOU TELL IF YOU'RE ON EMERGENCY TAX?
Look at the tax code on your payslip.
You might see something like:
• 1257L W1: Week 1 basis.
• 1257L M1: Month 1 basis.
• 1257L X: Non-cumulative basis.
Some payroll systems may also display NONCUM.
These codes tell payroll to calculate your Income Tax using only the current pay period, rather than taking your previous earnings and tax deductions from the same tax year into account.
That's an important distinction!
SO WHY COULD YOU PAY MORE TAX?
Imagine you've started a new job halfway through the tax year.
Under a normal cumulative tax code, payroll considers your taxable earnings, allowances and Income Tax already paid during the tax year.
However, on a Week 1 or Month 1 basis, payroll calculates the tax for that individual pay period without bringing those earlier figures into the calculation.
Depending on your circumstances, you could initially pay more tax than necessary.
You could also pay less.
WHAT ABOUT TAX CODES BR AND 0T?
These are sometimes described as emergency tax codes in everyday conversation, but they have their own meanings.
BR generally taxes all income from that employment at the basic rate, while 0T provides no Personal Allowance against that income.
Neither automatically means HMRC has made a mistake. For example, BR can be appropriate for a second job.
WILL YOU GET YOUR MONEY BACK?
If HMRC issues a corrected cumulative tax code, your employer's payroll system will generally recalculate your PAYE position using the relevant year-to-date information.
This can result in a tax refund through your wages or additional tax being collected.
In other circumstances, HMRC may arrange a refund separately.
SO WHAT SHOULD YOU DO?
Check your tax code on your payslip, make sure your employer has your P45 or completed starter checklist where appropriate, and check your details through your HMRC Personal Tax Account.
Don't assume that a large tax deduction is correct simply because it appeared on your payslip.
And equally, don't assume it's wrong without understanding how it was calculated.
WHY SHOULD YOU CARE?
Because understanding your tax code helps you understand your take-home pay.
A temporary coding basis can make a noticeable difference to what reaches your bank account, particularly when changing jobs.
Have you ever been put on emergency tax? How long did it take to get your tax code corrected?
Official HMRC guidance:
https://www.gov.uk/tax-codes/emergency-tax-codes
Check your tax code:
https://www.gov.uk/tax-codes
Payroll Unpacked: Your pay. Your deductions. Your rights. Explained.