Tax codes UK 2025/26: Full list of HMRC codes from April 2025 - what they mean, deductions and 1257L explained

While many of us are aware of tax codes, most are completely in the dark as to what they mean - and if we even have the correct one. Tax codes, which are usually visible on your pay slip, put you - as a 'worker' - into a category which dictates the amount of tax you pay on your wages, pension, and so on.

There are many, many different tax codes, and mistakes are made fairly frequently, leaving some paying more tax than they should be - or vice versa.

HM Revenue and Customs (HMRC) described your tax code as being "used by your employer or pension provider to work out how much Income Tax to take from your pay or pension", and that it tells your employer which tax code to use.

You can find out your tax code by looking at a recent pay slip, or by creating an account with the HMRC online, or use the HMRC app.

What does my tax code mean?

A tax code is made up of numbers and letters - and there are a few covering most people in the UK. The most common tax code is 1257L - the tax code currently used for most people who have one job or pension.

The numbers (1257) designate the amount of 'tax free' income you are allowed. In this case, it is the standard amount, of £12,570 - shortened to 1257.

"HMRC works out your individual number based on your tax-free Personal Allowance and income you have not paid tax on (such as untaxed interest or part-time earnings)," the HMRC says. "They also consider the value of any company benefits (such as a company car)."

For example, if you are entitled to the standard tax-free Personal Allowance of £12,570, but you also get medical insurance from your employer, this will change your tax code - as medical insurance is a company benefit.

If, for example, the medical insurance benefit is £1,570, that would be taken away from your personal allowance, leaving you with a tax-free Personal Allowance of £11,000.

Your tax code would then change to 1100L.

What does the letter mean on my tax code?

Following your numerical code, you will notice a letter on the end of your tax code. The letter, according to HMRC, refers to your "situation and how it affects your Personal Allowance".

Here is a breakdown of what different letters mean, from HMRC:

• L: You’re entitled to the standard tax-free Personal Allowance
• M: Marriage Allowance: you’ve received a transfer of 10% of your partner’s Personal Allowance
• N: Marriage Allowance: you’ve transferred 10% of your Personal Allowance to your partner
• T: Your tax code includes other calculations to work out your Personal Allowance
• 0T: Your Personal Allowance has been used up, or you’ve started a new job and your employer does not have the details they need to give you a tax code
• BR: All your income from this job or pension is taxed at the basic rate (usually used if you’ve got more than one job or pension)
• D0: All your income from this job or pension is taxed at the higher rate (usually used if you’ve got more than one job or pension)
• D1: All your income from this job or pension is taxed at the additional rate (usually used if you’ve got more than one job or pension)
• NT: You’re not paying any tax on this income
• S: Your income or pension is taxed using the rates in Scotland
• S0T: Your Personal Allowance (Scotland) has been used up, or you’ve started a new job and your employer does not have the details they need to give you a tax code
• SBR: All your income from this job or pension is taxed at the basic rate in Scotland (usually used if you’ve got more than one job or pension)
• SD0: All your income from this job or pension is taxed at the intermediate rate in Scotland (usually used if you’ve got more than one job or pension)
• SD1: All your income from this job or pension is taxed at the higher rate in Scotland (usually used if you’ve got more than one job or pension)
• SD2: All your income from this job or pension is taxed at the advanced rate in Scotland (usually used if you’ve got more than one job or pension)
• SD3: All your income from this job or pension is taxed at the top rate in Scotland (usually used if you’ve got more than one job or pension)
• C: Your income or pension is taxed using the rates in Wales
• C0T: Your Personal Allowance (Wales) has been used up, or you’ve started a new job and your employer does not have the details they need to give you a tax code
• CBR: All your income from this job or pension is taxed at the basic rate in Wales (usually used if you’ve got more than one job or pension)
• CD0: All your income from this job or pension is taxed at the higher rate in Wales (usually used if you’ve got more than one job or pension)
• CD1: All your income from this job or pension is taxed at the additional rate in Wales (usually used if you’ve got more than one job or pension)

If your tax code has a ‘K’ at the beginning, it means you have income that is not being taxed another way that is worth more than your tax-free allowance. HMRC says this happens most commonly when people are paying tax owed from a previous year through wages or pension, getting benefits you need to pay tax on, your employer or pension provider takes the tax due on the income that has not been taxed from your wages or pension.

Employers and pension providers cannot take more than half your pre-tax wages or pension when using a K tax code.

What are 'emergency' tax codes?

Tax codes ending with ‘W1’ or ‘M1’ or ‘X’ are emergency tax codes. For example:

• 1257L W1 - used when you’re paid weekly
• 1257L M1 - used when you’re paid monthly
• 1257L X - used if when you get paid varies

An emergency tax code can be imposed in a number of circumstances, such as:

if HMRC does not get your income details in time after a change in circumstances such as:

• a new job
• working for an employer after being self-employed
• getting company benefits or the State Pension

Emergency tax codes are temporary. HMRC will usually update your tax code when you or your employer give them your correct details, but this can take up to 35 days.

"If your change in circumstances means you have not paid the right amount of tax, you’ll stay on the emergency tax code until you’ve paid the correct tax for the year," an HMRC guide said. "Your employer can help you update your tax code by sending details about your previous income or pension to HMRC.”

If you’ve started a new job, you should give your employer your P45 from your previous job. If you do not have a P45, your employer should ask you to complete a form to give details of any previous employments or benefits.

How to update your tax code

HMRC should automatically update tax codes as circumstances change. However, if information about your income is incorrect, you may be given an incorrect tax code. To correct it, make sure HMRC has up-to-date details about your income.

If you think your tax code is wrong, you can use the Check your Income Tax online service to update your employment details, or tell HMRC about a change in income that may have affected your tax code.

After you update your details, HMRC will tell you if they change your tax code. They will also tell your employer or pension provider that your tax code has changed - and it should appear on your next pay slip.

What if I've paid too much tax?

If HMRC finds you have paid too much - or too little - you will either get a tax refund, or pay the tax you owe. You will be sent a tax calculation letter (known as a ‘P800’), or a Simple Assessment letter.