UK Tax Code Checker (2026/27)
Paste the code from your payslip and see what it actually means: the tax-free allowance behind it, whether it is an emergency code, and the Income Tax and take-home pay it produces against the standard code.
What your tax code means
You're entitled to the standard tax-free Personal Allowance
An estimate for guidance only, not financial advice. Your code can include adjustments for company benefits, untaxed income or underpaid tax from an earlier year, so it will not always match the standard allowance. Check your code on your payslip, P60 or personal tax account.
What the number in a UK tax code means
HMRC works out your tax-free income for the year, drops the final digit and replaces it with a letter. That is the whole rule: multiply the number by 10 and you have the pay you can take before Income Tax starts.
The standard code for 2026/27 is 1257L, because the
Personal Allowance is £12,570. A lower number means something has been
taken off your allowance — most often a company car, medical insurance or tax owed from an
earlier year. A higher number means something has been added, such as allowable expenses or
a Marriage Allowance transfer from your partner.
National Insurance ignores your tax code completely. It is calculated from what you actually earn in each pay period against its own thresholds, which is why a wrong code moves the tax line on your payslip and leaves the National Insurance line alone.
Every UK tax code letter and what it means
The wording below is HMRC's own, from the GOV.UK tax code guidance.
| Code | Where it sits | What HMRC says it means | Example |
|---|---|---|---|
L | Letter after the number | You're entitled to the standard tax-free Personal Allowance | 1257L |
M | Letter after the number | Marriage Allowance: you've received a transfer of 10% of your partner's Personal Allowance | 1257M |
N | Letter after the number | Marriage Allowance: you've transferred 10% of your Personal Allowance to your partner | 1257N |
T | Letter after the number | Your tax code includes other calculations to work out your Personal Allowance | 1257T |
0T | Whole code, no number | Your Personal Allowance has been used up, or you've started a new job and your employer does not have the details | 0T |
BR | Whole code, no number | All your income from this job or pension is taxed at the basic rate | BR |
D0 | Whole code, no number | All your income from this job or pension is taxed at the higher rate | D0 |
D1 | Whole code, no number | All your income from this job or pension is taxed at the additional rate | D1 |
NT | Whole code, no number | You're not paying any tax on this income | NT |
K | Letter before the number | You have income that you are not paying tax on which is more than your Personal Allowance | K500 |
S | Letter at the very start | Your income or pension is taxed using the rates in Scotland | S1257L |
C | Letter at the very start | Your income or pension is taxed using the rates in Wales | C1257L |
An S prefix moves you onto
Scottish Income Tax rates, which have six bands rather than
three. A C prefix means Welsh rates, which currently match those in England and
Northern Ireland.
Emergency tax codes: W1, M1 and X
An emergency code is a normal code with a period marker on the end. The marker makes it non-cumulative: instead of your tax being based on your total income so far in the tax year, it is worked out on what you are paid in that week or month alone, as if you were paid that amount every period of the year.
| Ending | When it is used |
|---|---|
W1 | used when you're paid weekly, for example 1257L W1 |
M1 | used when you're paid monthly, for example S875L M1 |
X | used when your pay dates vary, for example C663L X |
That is why a new starter who is paid a large first month, or who starts partway through the year, often overpays. On a cumulative code the unused allowance from earlier months is available to you; on an emergency code it is not.
Emergency codes usually appear when a new employer does not have your previous income and tax details. Handing over your P45 is the normal fix, and HMRC typically updates the code within 35 days of having details from both employers. Any overpayment comes back through payroll once the code goes cumulative.
What the wrong tax code actually costs
Monthly take-home pay for 2026/27 under the four codes people most often find on a payslip. Same salary, same National Insurance — only the code changes.
| Salary | 1257L | 0T | BR | D0 |
|---|---|---|---|---|
| £20,000 | £1,493/mo | £1,284/mo | £1,284/mo | £950/mo |
| £25,000 | £1,793/mo | £1,584/mo | £1,584/mo | £1,167/mo |
| £30,000 | £2,093/mo | £1,884/mo | £1,884/mo | £1,384/mo |
| £35,000 | £2,393/mo | £2,184/mo | £2,184/mo | £1,600/mo |
| £45,000 | £2,993/mo | £2,662/mo | £2,784/mo | £2,034/mo |
| £55,000 | £3,538/mo | £3,119/mo | £3,407/mo | £2,491/mo |
| £70,000 | £4,263/mo | £3,844/mo | £4,382/mo | £3,216/mo |
On £35,000, a 0T code takes £2,514 a year more than 1257L, and a BR code
takes £2,514 more, because both tax the pay your allowance
would otherwise have covered.
If the code is wrong you are not losing the money permanently — it comes back once HMRC corrects it. But it comes back at HMRC's pace, not yours, so it is worth checking the code on every new job. To see the rest of your payslip, use the full take-home pay calculator.
UK tax code FAQ
What does tax code 1257L mean?
1257L is the standard UK tax code for 2026/27. HMRC's own description of the L suffix is "You're entitled to the standard tax-free Personal Allowance". The number is your tax-free pay with the last digit removed, so 1257 means £12,570 of tax-free income across the year — about £1,048 a month before Income Tax starts.
How do I work out the allowance from my tax code?
Multiply the number by 10. A code of 1000L is £10,000 of tax-free pay, and 863L is £8,630. A K code works the other way round: K500 adds £5,000 to the pay you are taxed on instead of taking it off, which is how HMRC collects tax on company benefits or untaxed income worth more than your allowance.
What is an emergency tax code?
An emergency code ends in W1, M1 or X. Instead of your tax being based on your total income so far in that tax year, GOV.UK explains it is worked out based on what you're paid in that week or month only — you get taxed as if you're paid that amount every week or month of the year. It usually appears when a new employer does not have your previous income and tax details.
Why is my second job taxed at 20% from the first pound?
Because your Personal Allowance is normally attached to your main job, so the second one gets a BR code — HMRC's wording is "All your income from this job or pension is taxed at the basic rate". On £35,000 a BR code costs £2,514 a year more than 1257L. That is correct if the allowance really is being used elsewhere, and wrong if it is not.
How do I fix a wrong tax code?
Give your new employer the P45 from your previous job, which GOV.UK says can help take you off the emergency tax code. Otherwise contact HMRC directly. Once they have details from both employers, HMRC typically updates the code within 35 days, and any overpaid tax comes back through payroll rather than needing a separate claim.
Does my tax code change my National Insurance?
No. A tax code only tells your employer how much Income Tax to deduct. National Insurance is worked out separately from your actual earnings in each pay period, against its own thresholds, so a wrong tax code never changes your NI line — only the tax line.
What does an S or C at the start of my tax code mean?
S means your income is taxed using the rates in Scotland, and C means it is taxed using the rates in Wales. Welsh rates currently match those in England and Northern Ireland, so a C code produces the same figures. An S code does not: Scotland has six bands rather than three, and its flat-rate codes map to different bands, so SD0 is the Scottish intermediate rate rather than the higher rate.