UK tax-code guide
UK tax codes explained
A PAYE tax code tells your employer's payroll system how to calculate Income Tax from that job or pension. It does not, by itself, show your final tax position for the year.
In short
Different tax codes can be completely normal, especially after changing jobs, receiving benefits, having more than one income or living in Scotland or Wales. Check the code against HMRC's record before assuming a payslip is wrong.
Common codes you may see
- 1257L is a common standard code, but the number can change between tax years or personal circumstances.
- BR taxes all pay from that employment at the basic rate. It is often used for a second job.
- D0 and D1 tax all pay at the higher or additional rate respectively.
- 0T means no Personal Allowance is set against that employment; payroll generally uses the tax bands without an allowance.
- K codes can apply where HMRC needs more tax collected through PAYE because deductions from allowances exceed allowances.
- S and C prefixes identify Scottish and Welsh income-tax treatment.
What M1, W1 and X mean
These markers normally mean a week 1 or month 1 basis. Payroll looks at the current pay period rather than reconciling tax against earlier pay in the tax year. This can be temporary after a job change or an HMRC update.
Why a code may change
HMRC can change a code when it receives information about benefits, taxable income, estimated untaxed income, a previous underpayment, Marriage Allowance or another employment. A payslip can also be using a temporary code while HMRC receives starter information.
What to do if you are unsure
- Check the code on your payslip and in your HMRC Personal Tax Account.
- Make sure HMRC knows which job is your main employment if you have more than one.
- Ask HMRC about a code you think is wrong; your employer normally must use the code HMRC issues.
Use the UK tax-code checker for a plain-English explanation of common codes. HMRC's guidance on types of tax code and special cases gives the official payroll detail.