UK tax codes explained

Every UK tax code and the tax it takes on £30,000

Income Tax a year for 2026/27 if a £30,000 salary were taxed under each code, with the same pay every month.

Step 1: the prefix

S means you pay Scottish Income Tax (six bands from 19% to 48%). C means Welsh Income Tax, which uses the same 20%, 40% and 45% rates as England and Northern Ireland for 2026/27. No prefix means England or Northern Ireland rates.

Step 2: the number

HMRC starts with your £12,570 Personal Allowance, takes off things like company benefits, untaxed income or tax owed, and adds reliefs such as work expenses or Marriage Allowance. It then drops the last digit. GOV.UK's example: £1,570 of medical insurance leaves £11,000, so the code is 1100L.

Step 3: the letter

L is the standard allowance. M means you received Marriage Allowance and N means you gave it. T means HMRC must review the code before changing it, often because your allowance is reduced. P and Y are no longer used.

Step 4: anything at the end

W1 (weekly), M1 (monthly) or X (pay dates vary), or NONCUM on a payslip, means an emergency code: each payment is taxed on its own, ignoring pay and tax earlier in the year. It is usually temporary after starting a job.

Codes that break the pattern

BR taxes everything at 20%, D0 at 40% and D1 at 45% (SD0 to SD3 in Scotland at 21% to 48%), 0T gives no tax-free pay, NT takes no tax, and a K code adds an amount to your pay because your deductions are bigger than your allowance.

If you think this code is wrong

HMRC gives you a separate code for each job or pension, and changes it when your income or circumstances change. 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.)

What does your tax code mean?

Tax codes explained one by one

• 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%)
• K codes tax code (Untaxed income or deductions bigger than your allowance)
• NT tax code (No tax taken from this job or pension)

Tax code checker · Salary after tax calculator · What does your tax code mean?

Common questions