Tax code C — Welsh income tax bands apply
If your tax code starts with C (for example C1257L), HMRC has classified you as a Welsh taxpayer for 2026/27. Your employer applies the Welsh Rate of Income Tax (WRIT), which is set each year by the Senedd. For 2026/27 the Welsh basic (20%), higher (40%) and additional (45%) rates remain aligned with the rest-of-UK rates, so the in-payslip deduction is the same as 1257L.
What this code means
Per gov.uk's Welsh-tax guidance, the C prefix (“C” for Cymru) is the payroll mechanism that tells your employer to apply the Welsh Rate of Income Tax. Mechanically, HMRC subtracts 10 percentage points from the UK basic, higher and additional rates and the Senedd adds its own rate back on top — for 2026/27 the Senedd has continued to set the Welsh rates at 10p each, leaving the combined rates at 20%, 40% and 45%, the same as rUK. The C prefix therefore affects who receives the tax revenue (Welsh Government for the Welsh portion) but not what is taken from your payslip.
This alignment has held since the Welsh Rate of Income Tax was introduced in April 2019. The Senedd could choose to diverge in future, in which case the C prefix would produce a different PAYE figure to 1257L. For now, C1257L and 1257L produce the same PAYE deduction. The personal allowance, National Insurance and student loan thresholds remain UK-wide.
- C = Cymru / Welsh taxpayer. Bands above the allowance follow the Welsh Rate of Income Tax.
- Currently aligned with rUK. Senedd has kept rates at 10p each year since 2019.
- Personal allowance unchanged. Still £12,570 — set by the UK Government.
Who gets a C-prefix code
Per HMRC, the C prefix attaches to a code based on Welsh taxpayer status, which itself depends on where your main home is located across the year. The most common scenarios are below.
- Your main home is in Wales for most of the tax year
- Per HMRC's Welsh-taxpayer test, residency is decided by where your main residence sits across the year — not your employer's location or your day-to-day movements. If your main home is in Wales for more than half of the tax year, HMRC will normally apply the C prefix.
- You moved to Wales during the tax year
- A mid-year move triggers HMRC to reassess. If the larger part of the year is spent in Wales after the move, you become a Welsh taxpayer for that year. Update your address in the HMRC personal tax account when you move so the C prefix lands on the next coding notice.
- You have a Welsh address on HMRC record
- HMRC looks at the address on file. If you have moved into Wales and updated your record, the C prefix is normally applied automatically. If you have moved out of Wales but the address has not changed, the C prefix can persist incorrectly.
- Your employer is in Wales but you live elsewhere
- Not a trigger. Welsh taxpayer status follows the employee's residency, not the employer's location. Per HMRC, working at a Cardiff or Swansea office while living in Bristol does not give you a C prefix.
- HMRC residency determination for complex cases
- For people with multiple homes or who travel regularly for work, HMRC may issue a formal Welsh-taxpayer determination after reviewing day counts and main-home location. The C prefix then applies until circumstances change materially.
Worked example — £30,000 gross on C1257L
£30,000 gross salary in 2026/27. Personal allowance £12,570 leaves £17,430 taxable. Welsh bands aligned with rUK at the basic rate:
| Step | C1257L (Welsh, 2026/27) |
|---|---|
| Gross pay | £30,000 |
| Personal allowance | £12,570 |
| Taxable pay | £17,430 |
| PAYE: rUK 10p + Welsh 10p = 20% | £3,486 |
| Net result | Identical to 1257L while Welsh rates remain 10p |
The Welsh portion of that £3,486 (£1,743 in this example) flows to the Welsh Government; the other £1,743 goes to the UK Treasury. From your perspective, the deduction looks the same as it would under 1257L — but the C prefix is doing real work behind the scenes by directing the Welsh share of revenue. If the Senedd ever diverges from 10p, the figures on your payslip would change accordingly.
Common mistakes & red flags
- C prefix after moving out of Wales. HMRC has not updated your record — change your address in the personal tax account.
- No C prefix after moving to Wales. You may be a Welsh taxpayer but coded as rUK. Update HMRC.
- C prefix because of employer location. Welsh prefix follows the employee, not the employer. If the only reason is “my office is in Cardiff”, the code may be wrong.
- Different prefixes across two jobs. Only one residency applies. If one employer has you on C and another does not, push HMRC to align the prefix.
What to ask payroll
- “Which HMRC coding notice set the C prefix?”
- “What address is on my employee record?”
- “Are Welsh rates being applied — and at what percentages this year?”
- “If HMRC switches the prefix mid-year, will payroll handle the in-year refund?”
- “Can you confirm year-to-date pay and PAYE?”
How to fix it if the C prefix looks wrong
- Update your address with HMRC. Sign in to your HMRC personal tax account.
- Tell HMRC about a move. Complete the change-of-address notification if you have moved into or out of Wales.
- Wait for a new code. HMRC reissues with or without the C prefix as appropriate.
- Refund through payroll. While rates remain aligned with rUK the cash impact is usually nil, but the allocation of revenue between governments shifts to match your actual residency.
Frequently asked questions
- What does a C prefix on a tax code mean?
- Per gov.uk, the C prefix on a UK tax code (for example C1257L) means you are treated as a Welsh taxpayer for the year. Your employer applies the Welsh Rate of Income Tax (WRIT), which is set annually by the Senedd. For 2026/27 the Welsh basic, higher and additional rates remain aligned with the rUK rates of 20%, 40% and 45%.
- Is Welsh income tax higher than English?
- Not currently. Since the Welsh Rate of Income Tax was introduced in April 2019, the Senedd has chosen to keep the Welsh rates identical to the rUK rates each year — 10p of every pound paid in the basic, higher and additional rate bands is allocated to the Welsh Government, but the headline rate paid by employees is unchanged. The Senedd could alter this in future Budgets.
- How does HMRC decide if I am a Welsh taxpayer?
- Same residency test as Scottish taxpayers: your main home must be in Wales for the majority of the tax year. Employer location is not the test. Update your address with HMRC if you move into or out of Wales so the prefix is applied correctly.
- How much tax does C1257L imply on £30,000?
- Currently the same as 1257L: £30,000 minus £12,570 allowance = £17,430 taxable, all within the basic-rate band at 20%, producing about £3,486 of PAYE. The C prefix tells HMRC where to allocate the 10p of every basic-rate pound (Welsh Government rather than UK Treasury), but the deduction on your payslip is unchanged while rates remain aligned.
- How do I change a C prefix that is wrong?
- Sign in to your HMRC personal tax account and update your address. HMRC reissues a code with or without the C prefix as appropriate. Call HMRC PAYE on 0300 200 3300 if the change does not flow through after a couple of pay runs.
Related reading
- Tax code S — Scottish income tax
The sister prefix for Scottish taxpayers.
- Tax code 1257L — standard allowance
The non-prefixed equivalent.
- Tax code BR — flat 20%
May appear as CBR for Welsh second jobs.
- Every UK tax code, explained one page at a time
The full tax-code index hub.
- Wrong tax code checker
Run a guided check.
Last reviewed
Last reviewed:
Next review:
Reviewed each tax year and sooner if the Senedd diverges Welsh rates from rUK.
Educational guidance only — not regulated tax, financial or payroll advice. Verify the current Welsh Rate of Income Tax against gov.uk before acting. To run a real check, the wrong-tax-code checker is the place to begin.