Tax Code D1 Explained
Tax code D1 means all income from this source is taxed at the additional rate of 45% — the highest rate in the UK (for England, Wales and Northern Ireland). No Personal Allowance and no lower-rate bands apply. This is the steepest flat-rate code, used when your total income from other sources already exceeds the higher rate limit of £125,140.
What does tax code D1 mean?
Tax code D1 means all income from this employer is taxed at 45%, the highest UK rate. No allowances or lower bands apply. HMRC issues D1 when your total income from other sources already exceeds £125,140.
Who gets tax code D1?
High earners with multiple income streams — typically those whose combined income from other sources already exceeds £125,140. Their additional employment or pension income falls into the additional rate band automatically. It may also be applied temporarily when HMRC believes total income will exceed the additional rate threshold.
High deduction code: This code applies a high flat rate with no tax-free allowance, resulting in significantly less take-home pay than standard codes. Check that you have this code on the correct employment — it should only apply to secondary income sources.
Take-home pay on tax code D1 — 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 | £9,000 | £594 | £10,406 | 45.0% |
| £25,000 | £11,250 | £994 | £12,756 | 45.0% |
| £30,000 | £13,500 | £1,394 | £15,106 | 45.0% |
| £35,000 | £15,750 | £1,794 | £17,456 | 45.0% |
| £40,000 | £18,000 | £2,194 | £19,806 | 45.0% |
| £45,000 | £20,250 | £2,594 | £22,156 | 45.0% |
| £50,000 | £22,500 | £2,994 | £24,506 | 45.0% |
| £60,000 | £27,000 | £3,211 | £29,789 | 45.0% |
| £75,000 | £33,750 | £3,511 | £37,739 | 45.0% |
| £100,000 | £45,000 | £4,011 | £50,989 | 45.0% |
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 D1 vs 1257L: take-home comparison
How much more or less you take home on D1 compared to the standard 1257L code at the same gross salary. A negative number means less take-home pay.
| Gross Salary | 1257L Take-Home | D1 Take-Home | Difference |
|---|---|---|---|
| £20,000 | £17,920 | £10,406 | -£7,514 |
| £25,000 | £21,520 | £12,756 | -£8,764 |
| £30,000 | £25,120 | £15,106 | -£10,014 |
| £35,000 | £28,720 | £17,456 | -£11,264 |
| £40,000 | £32,320 | £19,806 | -£12,514 |
| £45,000 | £35,920 | £22,156 | -£13,764 |
| £50,000 | £39,520 | £24,506 | -£15,014 |
| £60,000 | £45,357 | £29,789 | -£15,568 |
| £75,000 | £54,057 | £37,739 | -£16,318 |
| £100,000 | £68,557 | £50,989 | -£17,568 |
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 D1, 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 D1 mean?
Tax code D1 means all income from this source is taxed at the additional rate of 45% — the highest rate in the UK (for England, Wales and Northern Ireland). No Personal Allowance and no lower-rate bands apply. This is the steepest flat-rate code, used when your total income from other sources already exceeds the higher rate limit of £125,140.
Who gets tax code D1?
High earners with multiple income streams — typically those whose combined income from other sources already exceeds £125,140. Their additional employment or pension income falls into the additional rate band automatically. It may also be applied temporarily when HMRC believes total income will exceed the additional rate threshold.
How much do I take home on tax code D1 earning £30,000?
On tax code D1 with a £30,000 salary, you take home £15,106 per year (£1,259 per month) after Income Tax of £13,500.
Is tax code D1 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 D1?
To change tax code D1, 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 D1 was applied in error?
If tax code D1 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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