Quick Tax Code Lookup
What is a Tax Code?
A tax code is a combination of numbers and letters (e.g., 1257L) used by your employer or pension provider to calculate the amount of Income Tax to deduct from your pay or pension.
The number in your tax code (multiplied by 10) represents your tax-free Personal Allowance. For example, 1257 means £12,570 tax-free income.
The letter(s) tell your employer how to adjust your allowance for different circumstances.
⚠️ If your tax code is wrong, you could be paying too much or too little tax. Check it regularly!
Tax Code 1257L Explained
1257L is the most common tax code in the UK for the 2025/26 tax year. If you have one job and no taxable benefits, this is likely your code.
Breaking it down:
- 1257 = Your tax-free Personal Allowance is £12,570 (1257 × 10)
- L = You're entitled to the standard tax-free Personal Allowance
With 1257L, your first £12,570 of annual income is tax-free. You then pay 20% tax on earnings between £12,571 and £50,270, and 40% on earnings above that.
Tax Code Letters Explained
L - Standard Personal Allowance
You're entitled to the standard tax-free Personal Allowance (£12,570 for 2025/26). This is the most common letter.
M and N - Marriage Allowance
Used when transferring Personal Allowance between married couples or civil partners.
- M: You've received 10% of your partner's allowance (code becomes 1394M)
- N: You've transferred 10% of your allowance to your partner (code becomes 1120N)
T - HMRC Review Required
HMRC needs to review your tax situation to calculate your allowance. This might be due to estimated income over £100,000 or other complex circumstances.
0T - No Personal Allowance
You have no tax-free allowance. All income is taxed. Common reasons:
- Your allowance is used up elsewhere
- You earn over £125,140 (Personal Allowance is fully withdrawn)
- You haven't provided employer with correct details
S - Scottish Tax Codes
If you live in Scotland, your code starts with S (e.g., S1257L). Scotland has different tax rates:
- 19% Starter rate: £12,571 - £14,876
- 20% Basic rate: £14,877 - £26,561
- 21% Intermediate rate: £26,562 - £43,662
- 42% Higher rate: £43,663 - £75,000
- 45% Advanced rate: £75,001 - £125,140
- 48% Top rate: Over £125,140
C - Welsh Tax Codes
If you live in Wales, your code starts with C (e.g., C1257L). Currently, Welsh tax rates are the same as England and Northern Ireland.
Second Job & Pension Tax Codes: BR, D0, D1
If you have multiple income sources, your Personal Allowance is usually applied to your main job. Additional jobs or pensions use these codes:
Example: You earn £35,000 from your main job (code 1257L) and £5,000 from a second job (code BR). Your main job uses your £12,570 allowance, so your second job income is taxed at 20% from the first pound.
K Tax Codes Explained
A K code (e.g., K100, K500) means you have income or benefits that need to be taxed, but the value exceeds your Personal Allowance.
Instead of giving you tax-free pay, a K code adds to your taxable income.
Common reasons for K codes:
- Company car benefit exceeds your Personal Allowance
- Private medical insurance provided by employer
- State Pension plus employment income
- Unpaid tax from previous years being collected
Example: K100 means £1,000 is added to your taxable income (100 × 10). If you earn £30,000, you're taxed as if you earned £31,000.
Emergency Tax Codes: W1, M1, X
If you see W1, M1, or X after your tax code (e.g., 1257L W1 or 1257L M1), you're on emergency tax.
Emergency tax means your pay is taxed on each pay period alone, without considering your year-to-date earnings or unused Personal Allowance.
Why you might be on emergency tax:
- Started a new job without giving your P45
- First job and didn't complete a Starter Checklist
- Returned to work after a gap in employment
- Receiving a new pension
How to fix it:
Give your P45 to your new employer, or complete the Starter Checklist. HMRC will update your tax code and any overpaid tax will usually be refunded automatically in your next payslips.
How to Check Your Tax Code
You can find your tax code on:
- Your payslip (usually near your National Insurance number)
- Your P60 (end of year certificate)
- Your P45 (if you recently left a job)
- Your Personal Tax Account on GOV.UK
- HMRC app
If you think your tax code is wrong, contact HMRC directly. Your employer cannot change it without an instruction from HMRC.
Complete Tax Code Reference
| Code/Letter | Meaning |
|---|---|
| L | Standard Personal Allowance |
| M | Marriage Allowance - received 10% extra |
| N | Marriage Allowance - transferred 10% away |
| T | HMRC review required |
| 0T | No Personal Allowance |
| K | Deductions exceed allowance (adds to taxable income) |
| BR | All income taxed at 20% |
| D0 | All income taxed at 40% |
| D1 | All income taxed at 45% |
| NT | No tax deducted |
| S (prefix) | Scottish tax rates apply |
| C (prefix) | Welsh tax rates apply |
| W1/M1/X (suffix) | Emergency/non-cumulative tax basis |
Frequently Asked Questions
What does tax code 1257L mean?
Tax code 1257L is the standard tax code for 2025/26. The number 1257 represents your tax-free Personal Allowance of £12,570 (multiply by 10). The letter L means you're entitled to the standard Personal Allowance. This is the most common tax code in the UK.
What does tax code D0 mean?
Tax code D0 means all your income from this source is taxed at 40% (the higher rate). This is typically used for a second job or pension where your Personal Allowance is already being used against your main income. No tax-free allowance is applied.
What does tax code BR mean?
Tax code BR (Basic Rate) means all income from this source is taxed at 20%. Like D0, it's used when your tax-free allowance is applied elsewhere, typically for second jobs or pensions. No Personal Allowance is given.
What is a K tax code?
A K code (e.g., K100) means you have taxable benefits or income that exceeds your Personal Allowance. Instead of giving you tax-free pay, HMRC adds the excess to your taxable income. Common reasons include company car benefits, medical insurance, or state pension combined with employment.
What does W1 or M1 in my tax code mean?
W1 (Week 1) or M1 (Month 1) means you're on an emergency or non-cumulative tax basis. Your tax is calculated on each pay period alone, ignoring what you've earned previously. This often happens when starting a new job without a P45. The overpaid tax is usually refunded automatically once HMRC updates your code.
How do I check if my tax code is correct?
Check your tax code on your payslip, P60, or via your Personal Tax Account on GOV.UK. If the number doesn't match your expected Personal Allowance (usually 1257 for £12,570), or if you have an unexpected letter, contact HMRC to verify. Common reasons for changes include benefits in kind, multiple jobs, or pension income.
See How Your Tax Code Affects Your Pay
A change in your tax code changes your monthly take-home pay. Use our calculator to model different scenarios and see exactly how much you'll take home.
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