What does my tax code mean?

How the numbers in your tax code work

The numbers show how much tax-free income you get from that job or pension in the tax year. Add a 0 to the end of the numbers to get the amount.

For 2026/27 (6 April 2026 to 5 April 2027), the standard Personal Allowance is £12,570, so the most common code is 1257L.

What 1257L means in pay

Example: you earn £2,500 a month on 1257L in England. £2,500 minus £1,047.50 leaves £1,452.50 taxed at 20%. That is £290.50 income tax a month, or £3,486 a year on a £30,000 salary.

Common tax code letters

Emergency tax codes

If your code ends in W1, M1 or X (for example 1257L M1), it is an emergency code. Your tax is worked out only on what you are paid in that week or month, not on your total income for the year. You may pay too much or too little.

You often get one when you start a new job. Giving your new employer your P45 helps. It can take up to 35 days from when you start for HMRC to update your code. If it is still not updated after that, check and update your details online or contact HMRC. If you overpaid, you can claim it back.

K codes

A code starting with K means you have income that is not taxed some other way, worth more than your allowance. This can come from company benefits like a car, State Pension or taxable state benefits, owing tax from an earlier year, or savings interest above your Personal Savings Allowance. Your employer or pension provider cannot take more than half your pay or pension before tax when using a K code.

What changes your code

• starting a new job, or income from an extra job or pension
• starting or stopping company benefits, such as a company car
• getting taxable state benefits, or a change in your weekly State Pension
• savings interest above your Personal Savings Allowance
• claiming Marriage Allowance or tax relief on work expenses
• owing tax because you were on the wrong code

How to check your tax code

• the HMRC app
• the "Check your Income Tax" online service
• your payslip
• a Tax Code Notice letter from HMRC

If you think it is wrong, sign in to the "Check your Income Tax" online service and update anything wrong or missing. This is the quickest way. If you cannot use it, contact HMRC.

If you live in Scotland, Wales or Northern Ireland

• Scotland: your code starts with S, so Scottish rates are used.
• Wales: your code starts with C, so Welsh rates are used.
• Northern Ireland: codes work the same as in England.

Related guides

• What are the Income Tax rates?
• How is a second job taxed?
• What is the HMRC app?
• How do I claim a tax refund?
• What is an HMRC compliance check and what should I do?

Where these figures come from

• Tax codes: overview (GOV.UK)
• What your tax code means (GOV.UK)
• Emergency tax codes (GOV.UK)
• Why your tax code might change (GOV.UK)
• If you think your tax code is wrong (GOV.UK)
• If you have a K in your tax code (GOV.UK)
• Income Tax rates and allowances 2026/27 (HMRC)