UK tax codes · 2026/27 tax year

K tax codes: what they mean

A K at the start of your tax code means you have income or deductions that are bigger than your tax-free Personal Allowance and are not already taxed, such as a company car, State Pension or tax owed from an earlier year. Instead of giving you tax-free pay, your employer adds an amount to your pay before working out the tax. K154, for example, adds about £1,550 a year, so on £25,000 you pay £5,310 rather than £2,486. Your employer cannot take more than half your pay in tax.

Tax code rules checked against GOV.UK and HMRC's PAYE Manual on 25 September 2026.

K154 adds

£1,550

to taxable pay a year

Tax on £25,000

£5,310

on K154

Tax on £40,000

£9,080

on K154

Most taken

50%

of pay each payday

K154 and K475 compared with 1257L in 2026/27

Income Tax a year. K154 adds £1,550 and K475 adds £4,760 to taxable pay, reading the number as HMRC's manual example does.

Salary	Tax on K154	Tax on K475	Tax on 1257L
£25,000	£5,310	£5,952	£2,486
£40,000	£9,080	£10,364	£5,486
£60,000	£17,080	£18,364	£11,432

The 50% limit in action

A pension of £6,000 a year on K1000, which adds £10,010. Without the limit the tax would be more than half the pension.

Pay	Taxable pay	Tax without the limit	Tax actually taken
£6,000	£16,010	£3,202	£3,000

How HMRC works out the number

HMRC's manual example: allowances of £12,570 and a company car benefit of £14,120 give minus £1,550. HMRC drops the last digit (155), takes 1 off (154) and adds a K, giving K154. So the number roughly tells you the amount added to your pay, divided by 10.

Why you have a K code

GOV.UK gives these examples: paying tax you owe from a previous year through your wages or pension, getting State Pension or taxable state benefits, getting company benefits such as a company car, and savings interest above your Personal Savings Allowance.

The 50% rule

GOV.UK says employers and pension providers cannot take more than half of your pre-tax wages or pension when using a K code. HMRC's manual says any shortfall is collected on a later payday if possible, or HMRC may look at other ways to collect it.

SK and CK codes

A K code with an S in front, such as SK100, is worked out at Scottish rates, and CK at Welsh rates. The amount added to your pay works the same way.

If you think this code is wrong

Check each item HMRC has used, such as the value of a company car or the State Pension figure, and update anything that has changed. Sign in to HMRC's Check your Income Tax service (gov.uk/check-income-tax-current-year) and check your jobs, pensions, benefits and expenses. HMRC then tells you and your employer any new code within 15 working days; it should show on your next or following payslip if you are paid monthly, or your third if weekly. If you cannot go online, call the Income Tax helpline on 0300 200 3300 (Monday to Friday, 8am to 6pm). After starting a new job, wait 35 days before calling.

Guides and definitions

High Income Child Benefit Charge: how it is worked out and cut (Guide)
How to read your payslip: every line explained, with an example (Guide)
Emergency tax: how it works and how to get your money back (Guide)
Emergency tax code (An emergency tax code, marked W1, M1 or X, taxes each payday on its own, as if you were paid that amount every period of the year.)
P11D (A P11D is the form UK employers send HMRC by 6 July to report each employee's taxable benefits and expenses that were not taxed through payroll.)
P60 (A P60 is the yearly summary of your pay and tax from one employer, due by 31 May if you work there on 5 April.)
Personal Allowance (The Personal Allowance is the income you can earn each UK tax year before Income Tax starts: £12,570 for 2026/27.)
Tax code (A UK tax code tells your employer or pension provider how much tax-free pay to give you; 1257L, meaning £12,570, is the most common.)

Check your own tax code and pay

Other tax codes explained

1257L tax code (Standard tax-free allowance of £12,570 on one job or pension)
Emergency codes (W1, M1, X) tax code (Emergency basis: each payment taxed on its own)
S1257L tax code (Standard allowance, taxed at Scottish rates)
C1257L tax code (Standard allowance, taxed at Welsh rates)
1257M / 1383M tax code (You receive £1,260 of Marriage Allowance from your partner)
1257N / 1131N tax code (You transfer £1,260 of Marriage Allowance to your partner)
BR tax code (All pay taxed at the 20% basic rate, no allowance)
0T tax code (No tax-free pay; all pay taxed through the bands)
D0 tax code (All pay taxed at the 40% higher rate)
D1 tax code (All pay taxed at the 45% additional rate)
SD0, SD1, SD2, SD3 tax code (Scottish flat-rate codes at 21%, 42%, 45% or 48%)
NT tax code (No tax taken from this job or pension)

Every UK tax code in one table · Salary after tax calculator · Check your own tax code and pay

Common questions

What does K mean in my tax code?

GOV.UK says a K means you have income you are not paying tax on which is more than your Personal Allowance. Your employer adds an amount to your pay so that the tax on that other income is collected through your wages or pension.

How do I read the number in a K code?

Multiply by 10 to get roughly the amount added to your taxable pay for the year. In HMRC's example, K154 comes from a £1,550 gap between a company car benefit of £14,120 and the £12,570 allowance.

How much tax will I pay on a K code?

On K154 you pay tax as if you earned £1,550 more. That is £5,310 on £25,000, £9,080 on £40,000 and £17,080 on £60,000, against £2,486, £5,486 and £11,432 on 1257L.

Can a K code take all my wages?

No. Tax taken on any payday cannot be more than half your gross pay for that period. On a £6,000 pension with K1000 the tax would be £3,202, but only £3,000 can be taken.

Why do pensioners get K codes?

The State Pension is taxable, and GOV.UK says tax owed on it is usually taken from your other income through your tax code. If it is bigger than your Personal Allowance, that other pension gets a K code so the extra tax is collected there.

Sources and assumptions

Income Tax for the 2026/27 tax year (6 April 2026 to 5 April 2027), with the same pay every payday for the whole year.
The code number is read as GOV.UK describes it: the tax-free amount with the last digit dropped (1257 = £12,570). Payroll tables can differ by a few pounds.
National Insurance, pension contributions and student loans are not included unless a table says so.
K codes are read as HMRC's PAYE11095 example: K154 adds £1,550, so the amount added is (number + 1) × 10.

These are estimates to help you read your tax code, not tax advice. HMRC and your employer's payroll decide the tax you actually pay.