Updated for the 2026/27 tax year
The 0T tax code
Your Personal Allowance has been used up, or you’ve started a new job and your employer does not have the details they need to give you a tax code
What it does to your pay
0T gives you no tax-free amount at all: every pound from this job or pension is taxable. It is not a flat rate, though — the normal bands still apply, so the rate steps up as the income does. That distinction is the difference between this code and the England and Northern Ireland flat-rate codes, and it is worth several hundred pounds on a middling income.
Source: Reg 7(3)(ca) — and this is the ONLY code designation any of the three instruments states as a literal string.
A worked example
On pay of £30,000 for the year, 0T makes £30,000 taxable and produces £6,000 of income tax. The standard code on the same pay would produce £3,486, so this code costs £2,514 more over the year.
- £30,000 at 20% = £6,000
Income tax only — National Insurance, student loan repayments and pension contributions are separate and are not included here.
How 0T is written on a payslip
0T is the code. Anything printed after it is a marker, and the markers this site recognises are W1, M1, X and NONCUM — HMRC’s payroll names for the non-cumulative basis, which the regulations set out at regs 26–31 and which the emergency-code page explains in full. Whether a marker changes anything for THIS code is a question for the regulation quoted above, not for the marker.
The space is optional and payslips print it both ways. 0T W1 and 0TW1 are the same string as far as this site is concerned: the checker upper-cases what you type and strips the spaces out before it looks the code up, so either spelling reaches this page.
One character in 0T is worth checking twice: the 0 is the DIGIT zero, not the letter O. Typed as OT it is not a code this site can decode — the checker answers “malformed” rather than guessing — and it is a common enough mistype that it is worth looking at your payslip again before concluding the code itself is wrong.
Is it right for you?
Check whether HMRC simply lacks your details. This code is also issued when a new employer has nothing to go on, in which case it usually corrects itself once your record catches up.
Whatever the answer, the code HMRC holds for you is the one that governs, and it is on your Personal Tax Account. If your tax code is wrong sets out how to get it changed.
Common questions
What does the 0T tax code mean?
Your Personal Allowance has been used up, or you’ve started a new job and your employer does not have the details they need to give you a tax code. It gives no tax-free amount at all, but the normal bands still apply, so the rate steps up as the income does.
How much tax does 0T take on £30,000 a year?
On pay of £30,000 for the year, 0T makes £30,000 taxable and produces £6,000 of income tax. The standard code on the same pay would produce £3,486, a difference of £2,514 over the year. Income tax only — National Insurance, student loan repayments and pension contributions are separate and are not included.
Is 0TW1 the same code as 0T?
Yes. W1, M1, X and NONCUM are the markers HMRC uses for the non-cumulative basis, and a marker after 0T leaves the code itself unchanged. The space is optional: this site's checker reads 0TW1 and 0T W1 identically, because it strips spaces before looking the code up.
Is it 0T with a zero, or OT with the letter O?
A zero. The 0 in 0T is the digit, and this site's checker treats OT as malformed rather than guessing which you meant — so if you typed it with the letter and got nothing back, that is why.
Independent tool not affiliated with HMRC. For your official code, log in to your Personal Tax Account. Check your tax code on GOV.UK.
Letters and law are not the same thing. The PAYE Regulations create these codes by describing what they DO — “the basic rate code”, “the nil tax code” — and, with one exception, never write down the letters HMRC prints on your payslip. The letters are HMRC’s naming for those functions. This site labels which is which on every page, and the sources page shows the search behind that statement.
The figures and rules on this site are taken from the Income Tax (Pay As You Earn) Regulations 2003, the Income Tax Act 2007 and HMRC’s published guidance, and are shown as they were found. They have not been signed off by a reviewer. Where the law and HMRC’s naming differ, the page says which is which rather than blending them. For anything that affects a decision, the cited document governs and this site does not.