What does the tax code 1257L mean?

1257 means £12,570 of tax-free pay a year from that job, the standard Personal Allowance for 2026/27, and L means you get the standard allowance. An S in front means Scottish rates; a C, Welsh rates.

What is an emergency tax code?

A code ending W1, M1 or X, such as 1257L M1, usually given when you start a job without a P45. Each payday is taxed on its own (non-cumulatively), so allowance from earlier months of the tax year isn't given to you and any overpayment isn't refunded through your pay; it comes back once HMRC issues a normal code or after the tax year ends.

Am I owed a tax refund?

If your code gave you less allowance than you're due, or taxed everything at one rate, you've probably overpaid. On £30,000 a year taxed on BR (all at 20%) instead of 1257L, about £2,514 a year too much is taken, so roughly £1,257 after six months. Check your code and income in the HMRC app or your personal tax account.

Tax code checker: what your code means, and whether it takes the right tax

Decode any PAYE tax code, see the tax it takes from a year's pay against the tax you owe, and roughly how much a wrong code has over- or under-collected so far. Your figures never leave your browser.

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Worked example

Computed when this page was built by the same engine that runs the calculator above, so the figures below and the live tool can never disagree. Change any input above to see your own.

Inputs
Tax code	BR
A year's pay from this job	£30,000
Months on this code	6

Results
Tax this code takes a year	£6,000
Tax owed if this is your only income	£3,486
Too much a year	£2,514
Overpaid after 6 months	£1,257

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Reading a tax code

Most codes are a number and a letter. The number, multiplied by ten, is the tax-free pay you get from that job in a year: 1257 is £12,570. The letter says why: L the standard allowance, M you receive Marriage Allowance from your partner, N you've given it to them, T something HMRC needs to review. A K code works the other way: its number, times ten, is added to your taxable pay, because untaxed income or benefits come to more than your allowance, and the tax taken each payday is capped at half your pay.

Some codes have no allowance at all. BR taxes everything at the basic rate, D0 at the higher rate and D1 at the additional rate (in Scotland D0 to D3 are the intermediate, higher, advanced and top rates): usual for a second job or pension. 0T gives no allowance but applies the bands; NT takes no tax. An S or C in front means Scottish or Welsh rates, and W1, M1 or X after makes it an emergency, non-cumulative code.

When a different code is right

A lower allowance isn't necessarily a mistake. HMRC reduces it to collect tax on a company car or medical insurance, untaxed income such as rent or savings interest, or tax you owe from an earlier year, and a second job usually gets BR or D0 because the main job uses the allowance. The checker compares your code with the standard allowance on the assumption that this job is your only income, so read a difference as a reason to check, not a verdict.

Education, not advice. Today's bands and rates; the allowance is the code's number × 10. Check your code and income in the HMRC app or your personal tax account at gov.uk, and contact HMRC if something is wrong. For a personal recommendation on your wider finances speak to an FCA-regulated financial adviser.

Sources

GOV.UK, Tax codes (what the letters mean, emergency codes).
GOV.UK, Income Tax rates and Personal Allowances.
GOV.UK, Scottish Income Tax.