Last updated: 14 October 2026
Your tax code is 647L: should it be higher?
Possibly. 647L was the emergency or standard code for 2010/11, when the Personal Allowance was £6,475. For 2026/27, the standard tax code is 1257L, which means a tax-free allowance of £12,570. If HMRC has given you a code well below 1257L, it may be collecting tax on something else, such as a company car, unpaid tax from an earlier year, or income it thinks you have. It could also be a mistake.
How tax codes work
The number in a tax code is your tax-free allowance divided by 10. The letter shows how it is applied.
| Code | Meaning |
| 1257L | Standard Personal Allowance of £12,570 |
| 1257L M1 or W1 | Emergency basis, worked out per pay period |
| BR | All pay taxed at 20%, often a second job |
| 0T | No allowance at all |
| K code | Deductions exceed allowances, so extra income is added |
| S or C prefix | Scottish or Welsh taxpayer |
Why your code might be lower than 1257L
- Benefits in kind: a company car or medical insurance reduces the allowance
- Underpaid tax: HMRC collects up to £3,000 of last year’s debt through your code
- Untaxed income: savings interest, rental income or state pension
- Second job: the allowance may be used on your main job
- Income over £100,000: the allowance is reduced by £1 for every £2 above £100,000
Why it might be higher
- Marriage Allowance received from your spouse (1383M)
- Professional subscriptions or job expenses allowed in your code
- Gift Aid or pension relief for higher-rate taxpayers
How to check
- Sign in to your personal tax account or the HMRC app
2. Look at the breakdown of your tax code for the current year
3. Check each adjustment, such as benefits or estimated income
4. Tell HMRC if anything is wrong; the code will be corrected and payroll will refund any overpaid tax
Example
Paul’s 2026/27 code is 647L. When he checks his account, he finds HMRC has estimated £61,000 of untaxed income because of interest from an old account he closed last year. He updates his estimated income online, and his code changes to 1257L. His next payslip includes a refund of tax overpaid so far.
Emergency codes
If you start a job without a P45, you may get an emergency code with M1 or W1. This stops the code using allowances from earlier in the year. HMRC usually sends the employer a correct code within a few weeks.
If you have paid too much tax
If a wrong code meant you overpaid in earlier years, HMRC usually sends a P800 calculation after the end of the tax year and repays you. You can claim refunds for up to 4 previous tax years. Check your personal tax account for each year, especially if you changed jobs, had a period of unemployment or started drawing a pension.
Common mistakes
- Ignoring a coding notice because the payslip looks roughly right
- Not telling HMRC when a company car or benefit ends
Frequently asked questions
Is 647L still in use?
No, it’s from 2010/11. If your payslip shows it, ask your employer to check.
How long does a code correction take?
Usually one or two pay periods.
Will I get a refund?
Yes, through payroll or after the year ends.
Can my employer change my code?
No, only HMRC can.
Related: new employee tax code with no P45, tax code changes for savings interest and HMRC refund letters and scams.
Talk to Accotax
Want this handled for you? Our team at Accotax can help with tax code checks. See our small business accountants service, or contact us for a free, no-obligation quote.
This page is general guidance based on HMRC rules for the 2026/27 tax year, checked against gov.uk on 14 October 2026. It is not personal advice, so speak to an accountant about your own situation.
