Tax codes one by one
C1257L tax code
The C marks a Welsh taxpayer. This year it changes where part of your tax goes, not how much you pay.
Tax-free pay from this job
£12,570 a year
- 1257 × 10 = £12,570, and the letter L means the standard tax-free Personal Allowance.
- Welsh rates
- Cumulative: allowance and bands build up through the tax year, so over- or under-payments correct themselves
| Tax-free pay each month | £1,048.26 |
| Tax over the year on £38,000 | £5,084.00 |
| That is, each month | £423.67 |
| With C1257L instead | £5,084.00 |
Estimate with HMRC’s payroll method and the same pay every month. Only HMRC can change your code.
C1257L is the tax code HMRC gives to a Welsh taxpayer with one job or pension and the standard allowance. The number 1257 means £12,570 of tax-free pay for 2026 to 2027, exactly as in England; the C tells the payroll to apply the Welsh rates of Income Tax. Those rates are built in two layers: the UK rates are cut by 10p in each pound for Welsh taxpayers, and the Senedd adds its own Welsh rates on top, as the Budget 2026 overview of tax rates explains. For 2026 to 2027 the result is 20, 40, 45% on the basic, higher and additional bands, the same as in England and Northern Ireland. That is why C1257L and 1257L take the same amount: £5,084.00 a year on a salary of £38,000, and £11,428.00 on £60,000. The C still matters: it records that the Welsh rates set by the Senedd apply to you, and those rates could move away from England's in a later year. The Welsh rates for 2027 to 2028 had not been published by 29 October 2026.
Welsh rates with a C code
Tax with C1257L
£5,084.00
| With 1257L | £5,084.00 |
| Difference | £0.00 |
The Welsh rates of income tax are 10p in each band, so the totals match England in 2026 to 2027.
Rules read on HMRC’s texts by Radif Partners · Editorial policy · Method
How the Welsh rates are put together
Wales does not set its own bands. It keeps the UK bands and allowance and changes the rates through a simple mechanism: for a Welsh taxpayer, the UK rates drop by 10p in the pound, and the Welsh rates set by the Senedd are added back. In 2026 to 2027 the Welsh rate is 10p in every band, so the totals match those of England. HMRC's PAYE specification carries separate Welsh values for every rate and band all the same, so payroll software can apply a different figure the year the Senedd chooses one. The specification dates the Welsh Rate of Income Tax from 6 April 2019 and states that it left the calculation rules unchanged: free pay, cumulative tax and the emergency basis work exactly as they do for any other code.
| Band | Income | Rate for Welsh taxpayers |
|---|---|---|
| Basic | £12,571 to £50,270 | 20% |
| Higher | £50,271 to £125,140 | 40% |
| Additional | over £125,140 | 45% |
Like the Scottish rates, the Welsh rates apply to wages, pensions and most other taxable income. Savings interest and dividends are taxed at the same rates as in the rest of the UK.
Tax with C1257L at different salaries
Because every rate matches, the comparison is short: the second and third columns are identical. The monthly figure is the first payslip of the year with steady pay, using the £1,048.26 of free pay that code 1257 gives each month.
| Yearly pay | With C1257L | With 1257L | Month 1 with C1257L |
|---|---|---|---|
| £18,000 | £1,084.00 | £1,084.00 | £90.20 |
| £30,000 | £3,484.00 | £3,484.00 | £290.20 |
| £50,000 | £7,484.00 | £7,484.00 | £623.60 |
| £90,000 | £23,428.00 | £23,428.00 | £1,952.06 |
Who gets the C, and what to do after a move
Living in Wales is what puts you on the Welsh rates. If you move in or out during the tax year, the Welsh rates apply only if Wales was where you lived the longest of any part of the UK between 6 April and 5 April. HMRC then backdates the change to the start of that year and the payroll adjusts the tax automatically. With a home in Wales and another in England, Scotland or Northern Ireland, HMRC needs to know which is the main one; possessions, family and where you are registered with a bank or doctor all point to it. Lorry drivers, offshore workers and members of the armed forces are the usual examples.
In each case the trigger is your address. Update it in your HMRC online account or through GOV.UK's change of details service, and HMRC adds or removes the C. The emergency code is the exception: there is one emergency code for the whole UK, so a new starter in Wales sees 1257L M1, not C1257L M1, until HMRC sends the proper code.
Other Welsh codes and the year ahead
Every code can carry the C. GOV.UK lists CBR for a second job at the Welsh basic rate of 20%, CD0 at 40% and CD1 at 45%, and C0T when the allowance is used up or details are missing. Marriage Allowance gives C1383M or C1131N. For 2027 to 2028, the UK Budget keeps the allowance at £12,570, but the Welsh rates are set with the Welsh budget and had not been published on 29 October 2026; until they are, the page on next year treats them as unknown.