Tax codes explained: what 1257L, BR, 0T and emergency codes mean
Your tax code tells your employer or pension provider how much tax-free pay you get before income tax starts. A wrong code is one of the most common reasons people pay too much tax, so it's worth knowing how to read yours.
The standard code: 1257L
Most people with one job have the code 1257L in 2026/27. The number is your tax-free personal allowance with the last digit removed, so 1257 means £12,570. The L means you get the standard allowance.
If your number is lower, HMRC is collecting something extra through your pay, such as tax on a company car, unpaid tax from a previous year, or untaxed income. If it's higher, you may be getting an extra allowance, such as marriage allowance or tax relief on work expenses.
Common letters and codes
| Code | What it means |
|---|---|
| L | Standard personal allowance |
| M | You've received 10% of your partner's allowance (marriage allowance) |
| N | You've given 10% of your allowance to your partner |
| T | HMRC needs to review items in your code |
| BR | All income from this job is taxed at 20%, usually used for a second job |
| D0 | All income from this job is taxed at 40% |
| 0T | No tax-free allowance at all, often used when HMRC lacks details |
| K | You have deductions bigger than your allowance, so extra income is added to your taxable pay |
| S or C | You pay Scottish or Welsh income tax |
Emergency tax codes
If your code ends in W1, M1 or X, you're on an emergency or "non-cumulative" code. This often happens when you start a new job without a P45. You get your allowance for each pay period, but none of the unused allowance from earlier in the tax year, so you can pay too much tax for a while. Once HMRC has your details it usually issues a corrected code and any overpayment comes back through your pay.
How to check and fix your code
- Find your code on your payslip or in your personal tax account on GOV.UK, or in the HMRC app.
- Check the income and benefits HMRC has recorded for you, and whether any old jobs are still showing as live.
- If something is wrong, update it in your personal tax account or contact HMRC. Your employer can't change your code; only HMRC can.
Any tax overpaid during the year is normally refunded automatically through your pay once your code is corrected, or by HMRC after the tax year ends.
Check what you should be getting
The take-home pay calculator assumes the standard 1257L code. If your payslip shows noticeably less, your tax code is the first thing to check.