UK Tax Codes Explained 2025/26
Your tax code tells your employer how much tax-free income you are entitled to. Understanding your tax code ensures you pay the right amount of tax — no more, no less. This guide explains every common tax code, what the letters and numbers mean, and what to do if yours is wrong.
Updated for the 2025/26 tax year. Tax code information sourced from HMRC.
What is a Tax Code?
A tax code is a combination of numbers and letters used by your employer (or pension provider) to calculate how much income tax to deduct from your pay. It is issued by HMRC and appears on your payslip, P45, P60, and in your Personal Tax Account.
The standard 2025/26 tax code
1257L
The number in your tax code represents your total tax-free allowance for the year, with the last digit removed. So 1257 means £12,570. Your employer divides this across the year (e.g. £1,047.50 per month) and only deducts tax on income above this amount.
The letter tells HMRC and your employer which type of allowance you have and which rules apply. The most common letter is L, meaning you have the standard Personal Allowance.
Common Tax Codes for 2025/26
This table covers all the tax codes you are likely to encounter on your payslip or tax correspondence.
| Tax Code | Meaning | Who it applies to |
|---|---|---|
| 1257L | Standard tax code for 2025/26 You get the full Personal Allowance of £12,570. This is the most common tax code — most employees with one job and no taxable benefits will have this code. | Most employees with one job |
| 1257L M1/W1 | Emergency tax code (non-cumulative) Tax is calculated on each pay period in isolation, without accounting for previous periods. Often applied when HMRC does not have your full employment history. Also shown as 1257L X. | New starters, job changers |
| BR | All income taxed at Basic Rate (20%) Used for second jobs or pensions where your Personal Allowance is already applied to your main income. All earnings from this source are taxed at 20%. | Second job or pension recipients |
| D0 | All income taxed at Higher Rate (40%) Used when your main employment uses your Personal Allowance and basic rate band, and this additional income falls entirely in the higher rate band. | Second/third income sources |
| D1 | All income taxed at Additional Rate (45%) Rare — used when all income from this source falls in the additional rate band (over £125,140 taxable income). | Very high earners with multiple sources |
| 0T | No Personal Allowance (tax on all income) Your entire income is taxed using the standard bands but with zero Personal Allowance. Applied when your allowance has been fully used elsewhere, or HMRC does not have enough information. Also used for incomes over £125,140 where the allowance is tapered to zero. | High earners, or when P45 not provided |
| NT | No Tax — all income tax-free No tax is deducted from this income source. Very rare — used for diplomats, certain pension arrangements, or where a double taxation agreement applies. | Diplomats, specific agreements |
| K code (e.g. K475) | You owe tax that exceeds your allowance A K code means you have taxable benefits (company car, medical insurance, etc.) or underpaid tax from a previous year that is being collected through your tax code. The number after K is the amount of income that must be added to your taxable pay. For example, K475 adds £4,750 to your taxable income. | Employees with taxable benefits or underpaid tax |
| S prefix (e.g. S1257L) | Scottish taxpayer Scottish income tax rates apply. You are a Scottish taxpayer if Scotland is your main place of residence. The 'S' is added to whatever your underlying code is. Scottish rates have 6 bands: Starter (19%), Basic (20%), Intermediate (21%), Higher (42%), Advanced (45%), Top (48%). | Residents of Scotland |
| C prefix (e.g. C1257L) | Welsh taxpayer Welsh income tax rates apply. Currently, Welsh rates are identical to England and NI rates, so a C1257L code results in the same tax as 1257L. The prefix exists because the Welsh Parliament has the power to vary rates in future. | Residents of Wales |
| L suffix | Standard Personal Allowance applies The most common suffix. Indicates you are entitled to the standard Personal Allowance (£12,570 in 2025/26). The number before 'L' represents your allowance with the last digit removed — so 1257L = £12,570 allowance. | Most taxpayers |
| M suffix | Marriage Allowance — you received a transfer You have received a transfer of 10% of your partner's Personal Allowance (£1,260), increasing your allowance to £13,830. Your tax code number would be 1383M. | Marriage Allowance recipients |
| N suffix | Marriage Allowance — you transferred allowance You have transferred 10% of your Personal Allowance (£1,260) to your partner, reducing your allowance to £11,310. Your tax code number would be 1131N. | Marriage Allowance transferors |
| T suffix | Other calculations needed HMRC needs to review your tax code, or there are items that need further calculation. Often used where the Personal Allowance has been reduced due to the £100K taper. | Various — review required |
How to Read Your Tax Code
Every tax code has a structure. Here is how to decode it step by step.
Step 1: Check for a prefix
If your code starts with S (Scotland), C (Wales), or K (deductions exceed allowance), this is a prefix that modifies how the rest of the code works.
Step 2: Read the number
The number represents your tax-free allowance with the last digit removed. Multiply by 10 to get your actual allowance. For example: 1257 = £12,570 tax-free. For K codes, the number is the amount added to your taxable income (e.g. K475 = £4,750 added).
Step 3: Read the suffix letter
The letter at the end tells you which category of allowance you have:
| Letter | Meaning |
|---|---|
| L | Standard Personal Allowance |
| M | Marriage Allowance — you received a transfer from your partner |
| N | Marriage Allowance — you transferred part of your allowance |
| T | Other items need review to calculate your allowance |
| S | Scottish income tax rates apply (prefix) |
| C | Welsh income tax rates apply (prefix) |
| K | Deductions exceed your allowance (prefix — added to taxable income) |
| BR | All income from this source taxed at 20% |
| D0 | All income from this source taxed at 40% |
| D1 | All income from this source taxed at 45% |
| NT | No tax deducted |
| 0T | No Personal Allowance — full tax on all income |
Step 4: Check for M1/W1/X
If your code ends with M1 (Month 1), W1 (Week 1), or X, it is a non-cumulative (emergency) code. Tax is calculated on each pay period separately, ignoring earlier payments. This often results in overpaying tax.
Decoding examples
1257L
- No prefix → England/Wales/NI rates
- 1257 × 10 = £12,570 tax-free allowance
- L = standard Personal Allowance
S1257L
- S prefix → Scottish income tax rates
- 1257 × 10 = £12,570 tax-free allowance
- L = standard Personal Allowance
K475
- K prefix → deductions exceed allowance
- 475 × 10 = £4,750 added to taxable income
- Common for company car or unpaid tax
1383M
- No prefix → England/Wales/NI rates
- 1383 × 10 = £13,830 tax-free allowance
- M = received Marriage Allowance transfer (+£1,260)
What to Do if Your Tax Code is Wrong
A wrong tax code means you could be paying too much or too little tax. Common signs of a wrong code include:
- Your take-home pay changed unexpectedly between pay periods
- You have a BR code on your only job (meaning you get no Personal Allowance)
- You have an emergency tax code (M1/W1/X) that has not been corrected
- Your code does not account for a benefit you no longer receive (e.g. old company car)
How to fix it
- Check your tax code online — log in to your Personal Tax Account on GOV.UK or use the HMRC app
- Contact HMRC — call the income tax helpline on 0300 200 3300 (Monday to Friday, 8am to 6pm) or use the webchat service
- Provide information — HMRC may ask about your employment, benefits, or other income to recalculate your code
- Refund — if you have overpaid, HMRC will usually issue a P800 tax calculation or adjust your code to spread the refund over the remaining tax year. You can also claim refunds online.
You can claim back overpaid tax for up to 4 years
If you have been on the wrong tax code and overpaid tax, HMRC can refund you for up to the current year plus the previous 4 tax years. Check your P60 for each year against what you should have paid.
Emergency Tax Codes
An emergency tax code is a temporary code used when HMRC does not have enough information about your tax situation. It is commonly applied when:
- You start a new job and your new employer does not have your P45
- You start receiving a company pension
- You start receiving employment benefits (e.g. company car)
Emergency codes are shown as:
- 1257L W1 — Week 1 basis (weekly pay)
- 1257L M1 — Month 1 basis (monthly pay)
- 1257L X — Non-cumulative basis
How emergency tax works
On an emergency code, your tax is calculated on each pay period in isolation. This means your employer does not take into account any tax you may have already paid (or not paid) in earlier periods. The result is often that you overpay tax, particularly if you were not working at the start of the tax year and have unused Personal Allowance from those months.
How long does emergency tax last?
In most cases, HMRC will automatically correct your tax code within 1–3 months of your employer sending them your details. If it has not been corrected after 3 months, contact HMRC directly. Any overpaid tax will be refunded, either through an adjusted tax code or a P800 refund after the tax year ends.
Speed up the process
You can help HMRC correct your code faster by giving your new employer your P45 from your previous job, or by completing a “starter checklist” (which replaced the P46 form). You can also update your details directly through your Personal Tax Account.