Tax Code CD0 Explained
CD0 is the Welsh equivalent of the D0 tax code — all income from this source is taxed at a flat 40% higher rate, with no Personal Allowance applied. The C prefix confirms the taxpayer is a Welsh resident. Since Welsh Income Tax rates match England rates for 2025-26, the take-home pay on CD0 is identical to D0. It is used when additional income falls into the higher rate band because the basic rate band is already used by the primary income source.
What does tax code CD0 mean?
Tax code CD0 is the Welsh version of D0. All income from this source is taxed at 40% with no Personal Allowance. Welsh rates match England for 2025-26, so take-home pay on CD0 is identical to D0.
Who gets tax code CD0?
Welsh residents with a second job or income source whose main employment already fills the entire basic rate band (up to £50,270). Every pound from the secondary source goes straight into the 40% higher rate band. The C prefix ensures HMRC accounts for this income as Welsh Rate of Income Tax.
Welsh Rate of Income Tax: Wales sets its own Welsh Rates of Income Tax (WRIT) via the Senedd. For 2025-26, Welsh rates are identical to England rates (20% / 40% / 45%), so take-home pay is the same. The C prefix tracks revenue separately for the Welsh Government.
Take-home pay on tax code CD0 — 2025-26 examples
Examples below show Income Tax and take-home pay at common salary levels. National Insurance (NI) is also shown separately — NI is not affected by your tax code and applies on the same basis for all employees.
| Gross Salary | Income Tax | NI (est.) | Take-Home | Effective IT Rate |
|---|---|---|---|---|
| £20,000 | £8,000 | £594 | £11,406 | 40.0% |
| £25,000 | £10,000 | £994 | £14,006 | 40.0% |
| £30,000 | £12,000 | £1,394 | £16,606 | 40.0% |
| £35,000 | £14,000 | £1,794 | £19,206 | 40.0% |
| £40,000 | £16,000 | £2,194 | £21,806 | 40.0% |
| £45,000 | £18,000 | £2,594 | £24,406 | 40.0% |
| £50,000 | £20,000 | £2,994 | £27,006 | 40.0% |
| £60,000 | £24,000 | £3,211 | £32,789 | 40.0% |
| £75,000 | £30,000 | £3,511 | £41,489 | 40.0% |
| £100,000 | £40,000 | £4,011 | £55,989 | 40.0% |
Take-home = Gross − Income Tax − National Insurance. No pension, student loan or other deductions included. NI calculated at 8% between £12,570–£50,270 and 2% above. Effective IT Rate shows Income Tax as a percentage of gross salary.
Tax code CD0 vs 1257L: take-home comparison
How much more or less you take home on CD0 compared to the standard 1257L code at the same gross salary. A negative number means less take-home pay.
| Gross Salary | 1257L Take-Home | CD0 Take-Home | Difference |
|---|---|---|---|
| £20,000 | £17,920 | £11,406 | -£6,514 |
| £25,000 | £21,520 | £14,006 | -£7,514 |
| £30,000 | £25,120 | £16,606 | -£8,514 |
| £35,000 | £28,720 | £19,206 | -£9,514 |
| £40,000 | £32,320 | £21,806 | -£10,514 |
| £45,000 | £35,920 | £24,406 | -£11,514 |
| £50,000 | £39,520 | £27,006 | -£12,514 |
| £60,000 | £45,357 | £32,789 | -£12,568 |
| £75,000 | £54,057 | £41,489 | -£12,568 |
| £100,000 | £68,557 | £55,989 | -£12,568 |
Both columns include Income Tax and National Insurance. No pension or student loan deductions. 1257L = standard Personal Allowance of £12,570.
If you have tax code CD0, here's what you should know
- Your tax code appears on your payslip, P60, and any correspondence from HMRC about your PAYE tax.
- Your employer uses this code to calculate how much Income Tax to deduct from each pay period — they do not set it themselves.
- If your circumstances change (new job, change in benefits, marriage allowance), your code should update automatically — but it is worth checking.
- You can view and update your tax code online via your Personal Tax Account at gov.uk.
- If you think your code is wrong, contact HMRC on 0300 200 3300 or use the HMRC app.
- An incorrect tax code can mean you overpay or underpay tax — overpayments are refunded, underpayments are collected in future years.
Frequently asked questions
What does tax code CD0 mean?
CD0 is the Welsh equivalent of the D0 tax code — all income from this source is taxed at a flat 40% higher rate, with no Personal Allowance applied. The C prefix confirms the taxpayer is a Welsh resident. Since Welsh Income Tax rates match England rates for 2025-26, the take-home pay on CD0 is identical to D0. It is used when additional income falls into the higher rate band because the basic rate band is already used by the primary income source.
Who gets tax code CD0?
Welsh residents with a second job or income source whose main employment already fills the entire basic rate band (up to £50,270). Every pound from the secondary source goes straight into the 40% higher rate band. The C prefix ensures HMRC accounts for this income as Welsh Rate of Income Tax.
How much do I take home on tax code CD0 earning £30,000?
On tax code CD0 with a £30,000 salary, you take home £16,606 per year (£1,384 per month) after Income Tax of £12,000.
Is tax code CD0 correct for me?
Your tax code is set by HMRC based on your individual circumstances. If you believe your tax code is wrong, contact HMRC on 0300 200 3300 or check your Personal Tax Account at gov.uk. An incorrect code could mean you are paying too much or too little tax.
How do I change tax code CD0?
To change tax code CD0, contact HMRC directly on 0300 200 3300 or update your details via your Personal Tax Account at gov.uk. Your employer cannot change your tax code — only HMRC can issue a new one. Once HMRC updates your code, they will notify your employer and the change will appear on your next payslip.
Will I get a refund if tax code CD0 was applied in error?
If tax code CD0 was applied incorrectly and caused you to overpay Income Tax, HMRC will refund the overpayment. This typically happens automatically via a P800 tax calculation sent after the tax year ends (April). For a faster refund, contact HMRC directly once the correct code has been issued. Overpayments can also be reclaimed through Self Assessment if you file a return.
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