Updated for the 2026/27 tax year
The K475 tax code
You have income that you are not paying tax on which is more than your Personal Allowance
What it does to your pay
A K code is the one that works the other way round. £4,750 is ADDED to your pay before the tax is worked out, rather than taken off it. It is used when untaxed income or taxable benefits come to more than your allowance, so there is no allowance left to reduce — instead the excess is treated as extra pay.
Because that can produce a large deduction on a small payslip, there is a cap: your employer may not deduct more than 50% of any payment, however much the tables say is due. The cap DEFERS the rest into the next payment rather than cancelling it, which is the part most explanations leave out.
Source: Reg 7(2) — "'K code' means a code which gives rise to additional pay or total additional pay to date." Additional pay is defined by reg 2(1) as an amount "to be ADDED to the relevant payments", the mirror of free pay, which is "subtracted".
A worked example
On pay of £30,000 for the year, K475 makes £34,750 taxable and produces £6,950 of income tax. The standard code on the same pay would produce £3,486, so this code costs £3,464 more over the year.
- £34,750 at 20% = £6,950
Income tax only — National Insurance, student loan repayments and pension contributions are separate and are not included here.
What the cap looks like on one payslip
On a monthly payment of £2,500 worked out on its own, the tables come to £579.17 while the cap is £1,250. The cap does not bite at this level, so the full amount is deducted.
How K475 is written on a payslip
K475 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. K475 W1 and K475W1 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.
Is it right for you?
Check what is being added and why. HMRC works the figure out from benefits, untaxed income and tax owed from earlier years; if any of those are wrong or out of date, the K number is too.
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 K475 tax code mean?
You have income that you are not paying tax on which is more than your Personal Allowance. It ADDS £4,750 to your pay before the tax is worked out, rather than taking an amount off.
How much tax does K475 take on £30,000 a year?
On pay of £30,000 for the year, K475 makes £34,750 taxable and produces £6,950 of income tax. The standard code on the same pay would produce £3,486, a difference of £3,464 over the year. Income tax only — National Insurance, student loan repayments and pension contributions are separate and are not included.
Is K475W1 the same code as K475?
Yes. W1, M1, X and NONCUM are the markers HMRC uses for the non-cumulative basis, and a marker after K475 leaves the code itself unchanged. The space is optional: this site's checker reads K475W1 and K475 W1 identically, because it strips spaces before looking the code up.
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.