Tax code 1257T explained

What does tax code 1257T mean?

The number in a tax code shows your tax-free pay: multiply it by 10 and add up to 9. For 1257T, the number is 1257, so your tax-free pay is about £12,570 a year. The letter T tells your employer how to treat the allowance.

Your tax code does not change National Insurance. It only affects income tax.

Income tax on typical salaries with code 1257T

The table shows income tax only, using England, Wales and Northern Ireland rates for 2026/27: 20% on the first £37,700 of taxable pay and 40% above that. National Insurance and student loan are not included.

Is 1257L right for you?

1257L is the standard code for most employees with one job and no other taxable income. It may be wrong if you have a second job, a company car, untaxed interest or income, or if you receive the Marriage Allowance. Check your payslip and tell HMRC if your circumstances change.

Emergency tax codes: W1, M1 and X

If HMRC does not have your details when you start a job, you may be given an emergency code such as 1257L W1 or 1257L M1. These calculate tax on each pay period alone, ignoring your pay so far this year, which can take too much tax at first. HMRC normally corrects it within a few pay periods once your employer sends the right information, and any overpayment is refunded.

What to do if your tax code looks wrong

• Check it on your payslip, P45 or P60, or in your personal tax account on GOV.UK.
• Tell HMRC about changes in income, benefits or a second job.
• If you have paid too much tax, HMRC will usually refund it after the end of the tax year, or earlier if the code is corrected.
• You can ask HMRC to correct a code that uses an emergency basis (W1, M1 or X).