What Is My Tax Code? How to Find It and Get a New One

How to find your tax code

You get a separate code for each job or pension. You can find yours in any of these places:

• On your payslip. It is usually near your name, pay period or National Insurance number, often labelled 'Tax code'.
• On a Tax Code Notice letter from HMRC, which is sent when your code changes.
• In the HMRC app, or by signing in to the Check your Income Tax for the current year service on GOV.UK.
• On your P45 if you have left a job, or your P60 at the end of the tax year.

Checking it online or in the app

Signing in is the quickest route because you can see the code and how it was worked out. GOV.UK says the service lets you check your tax code and Personal Allowance, see whether your code has changed, and update details of your income from jobs and pensions.

You can also find codes for previous tax years there, and sign up for paperless notifications so HMRC emails you when your code changes. You cannot use it if Self Assessment is the only way you pay Income Tax.

What your tax code means

Multiply the number by ten to get your tax-free pay for the year from that job. 1257L means £12,570, the standard Personal Allowance for 2026/27, and it is the code most people with one job are given. The letter tells your employer which rules to apply: L is the standard allowance, M and N relate to Marriage Allowance, BR taxes everything at the basic rate and 0T gives no allowance.

A lower number usually means something has been taken off your allowance, such as a company benefit or tax owed from an earlier year. A K code means the deductions are bigger than your allowance, so income is added instead.

Use the Tax Code Calculator to see what you would save

Tax codes explained: every letter and code

Signs your tax code may be wrong

Check your code if any of these apply:

• You started a new job without a P45 and your code ends in W1, M1 or X.
• You have a second job or pension and one of them is not on BR.
• Your code is lower than 1257L and you do not know why.
• You have recently had a pay rise, a new benefit, or started or stopped Marriage Allowance.
• Your payslip tax looks too high or too low for your pay.

How to get a new tax code

You cannot choose your own code, and your employer cannot change it. HMRC sets it using the information it holds about your income and benefits. Usually, a wrong code means HMRC has incorrect or missing details, so the fix is to correct those details.

• Sign in to the Check your Income Tax service, or open the HMRC app.
• Check your jobs, pensions, estimated taxable income, company benefits and expenses.
• Update anything that is wrong or missing, and claim tax relief on any employment expenses.
• If you have left a job and never got a P45, ask that employer for one, as this can help HMRC update your details.
• If you cannot use the online service, contact HMRC. If you started a job recently, GOV.UK advises waiting 35 days for HMRC to receive your new income details before you call.

What happens next

If your code needs to change, HMRC updates it and tells you and your employer the new code within 15 working days. If you are paid monthly, it should appear on your next or following payslip. If you are paid weekly, it should appear on your third payslip. If your payslip still shows the old code, ask your employer to check they have received the new one.

Once the right code is in use, any tax you overpaid is usually refunded through your pay. If you underpaid, HMRC normally collects it by adjusting your code over one or more tax years.

What is a P45 and why it matters for your code

If you are on an emergency code

An emergency code is a temporary code used when your employer does not have the details it needs. It does not change the tax you owe for the year, but you may be taxed too much until HMRC sends the right code. Giving your new employer your P45, or completing the starter checklist accurately, usually clears it up.

Back to the full tax codes guide