1257L is the standard tax code for 2026/27. It means you can earn £12,570 in the tax year before paying income tax, with no adjustments. In Scotland it’s S1257L, and in Wales C1257L.
What 1257L means
A tax code is an instruction to payroll, not a bill. It says how much of your pay is tax-free and how that tax-free pay is handed out over the year. Your employer does not know your allowance or your other income: it is given a code, and the code carries all of it.
The number is the tax-free pay for the whole year with the last digit dropped. The letter says which kind of allowance you have, and it is how HMRC changes every code of a kind at once when an allowance moves.
So 1257L means the standard allowance, in full, with nothing added and nothing taken away. It is the most common code in the UK because most employees are exactly that: one job, no untaxed income, no company benefits.
Where the number comes from
The Personal Allowance for 2026/27 is £12,570. Drop the last digit and you have 1257. HMRC's guidance for employers puts it the same way round: the number is the tax-free income for the year, divided by ten.
The allowance is frozen at £12,570 until April 2031, so the number in the standard code does not move while the freeze lasts. A code that has changed is therefore usually about you rather than about the Budget.
Each spring HMRC publishes P9X, which tells employers which codes to use from 6 April. It confirms the allowance, names 1257L as the emergency code, and tells employers to carry the previous year's authorised code forward for anyone not sent a new one — but never to carry forward a week 1 or month 1 marking.
How the code reaches each payslip
Your allowance is not held back until the end of the year. It is released a slice at a time, and that slice has a name in HMRC's tables: free pay.
On 1257L, a monthly pay period releases £1,048.26 of free pay and a weekly one £241.92. Pay above that in the period is taxable. Both are a little more than a plain twelfth or fifty-second of the allowance, because HMRC's Tables A value a code as its number times ten plus nine pounds, build codes above five hundred out of fixed units, and round each part up to the penny.
The code is normally used cumulatively: each payslip looks at the year so far rather than that period alone. By the sixth month you have had six months of free pay, and any left unused — you started late, you were off, your pay dropped — is still there to be given. That is why a refund often arrives through your pay rather than as a separate payment.
Taken across a full year, £30,000 on 1257L works out at £290.50 of income tax a month and £2,093.34 of take-home pay, once National Insurance is taken as well. An individual payslip can differ by pennies, because each period is worked out on its own rounded figures.
What the L means
L means you get the standard Personal Allowance. It is the suffix HMRC uses for the ordinary case, and it is why your code moves automatically when the allowance itself moves, without a new notice.
Two letters replace it when Marriage Allowance is in play, because it moves £1,260 of allowance from one spouse or civil partner to the other. The one who receives it has the letter M and the code 1383M; the one who gives it up has N and the code 1131N. The number moves because the allowance moved.
A prefix is a different thing. S in front of the code means the Scottish rates apply and C the Welsh ones, and neither changes the size of your allowance: S1257L gives the same tax-free pay as 1257L, and what differs is the ladder of rates above it.
When 1257L is wrong
HMRC changes a code when something it knows about does not fit the standard allowance: untaxed income such as savings interest or rent, a company benefit like medical cover or a car, tax owed from an earlier year, or a second job where the allowance is already used elsewhere.
Most of those lower the number: the benefit or the income comes out of your allowance, so more of each payslip is taxable. If what has to be collected is larger than the whole allowance, the code becomes a K code, which adds to your taxable pay instead of sheltering part of it.
Adjusted net income above £100,000 works differently again. Over that line the allowance falls by one pound for every £2 above it, so the number in the code falls as your income rises, and high enough up there is no allowance left at all and the code becomes 0T. Adjusted net income is not your salary: it is broadly your income from all sources, less the gross amount of any pension contributions given relief at source and of any Gift Aid donations.
A second job is the commonest case, and nothing has gone wrong: your allowance is given in full at the main job, so 1257L would be the wrong code at the second one, and that employer is sent BR and taxes every pound at 20%.
1257L with W1, M1 or X after it
1257L followed by W1, M1 or X is the same code used non-cumulatively. The allowance is unchanged; what goes is the memory of the year so far. Each payslip is worked out as though it were the first of the year, so unused allowance from earlier months is not given.
This is what people mean by emergency tax. P9X names 1257L as the emergency code for all employees, so the number is right even when the marking is costing you: it is the standard code with its memory switched off.
It usually ends by itself once HMRC has the full picture, and the balance is settled through your pay when the code goes cumulative, or after the tax year ends.
What your tax code does not decide
Your tax code is about income tax and nothing else. National Insurance is worked out on the earnings in each pay period against its own thresholds, with no code and no annual running total, so two people on 1257L with the same salary can pay different amounts if one is paid unevenly.
Student loan repayments work the same way: they come off earnings above your plan's threshold in the period you are paid, whatever the code says. Changing your tax code changes your income tax and leaves both of those where they were.
Is 1257L an emergency tax code?
On its own, no: plain 1257L is the ordinary cumulative code. With W1, M1 or X after it, yes — that is the emergency form, and P9X confirms 1257L is the emergency code employers use. The test is on your payslip rather than in the code: tax that stays flat month after month, whatever you earned earlier in the year, is a code running non-cumulatively.
Does 1257L mean I am paying the right amount of tax?
It means you are being given the standard allowance once, at that job. Whether that is right depends on what the code cannot see. The commonest fault is two jobs both coded 1257L: each employer gives the full allowance, so it is given twice, and tax is underpaid until HMRC changes one of the codes.
It runs the other way too: if your main job pays less than your allowance, part of it goes unused while a second job is taxed from the first pound. HMRC's check your Income Tax service shows what your code is built from, line by line, and is where a wrong figure is corrected.