Tax Code D1 Explained
All income from this job or pension taxed at 45% additional rate. Typically a second income for a top-rate taxpayer.
At a glance — D1
- Personal Allowance
- £0
- Region
- UK-wide (rUK / Wales)
- Cumulative?
- Yes
- Code type
- Flat-rate / special
What does D1 mean?
All your income from this job or pension is taxed at the additional rate of 45%.
How much tax will you pay on D1?
Annual income tax HMRC would deduct on 2025-26 rates for a range of salaries, assuming the full year on this code. National Insurance is additional and the same across the UK.
| Annual salary | England / Wales / NI — income tax | Effective rate | Take-home (pre-NI) |
|---|---|---|---|
| £20,000 | £9,000 | 45.0% | £11,000 |
| £30,000 | £13,500 | 45.0% | £16,500 |
| £50,000 | £22,500 | 45.0% | £27,500 |
| £80,000 | £36,000 | 45.0% | £44,000 |
| £100,000 | £45,000 | 45.0% | £55,000 |
For Scottish / rUK side-by-side, or to model your own salary, student loan and pension contributions, use the tax code checker.
Should you be on tax code D1?
D1 usually applies to a second job, pension or one-off payment. If you only have one source of income, you almost certainly should be on 1257L (or the S / C equivalent), so contact HMRC to correct it.
Related tax codes
BR — Basic Rate
All income from this job or pension is taxed at the 20% basic rate, with no Personal Allowance. Usually a second job or pension.
D0 — Higher Rate
All income from this job or pension taxed at 40% higher rate, with no allowance or basic rate band.
NT — No Tax
No tax deducted at source. Usually applies to non-UK residents, some pension situations, or specific tax-treaty arrangements.
1257L — Standard
The default HMRC tax code for most UK employees — gives you the full £12,570 tax-free Personal Allowance.
Check your own code: enter any HMRC tax code into the free tax code checker — it decodes the letters and number, shows your Personal Allowance, and estimates your take-home using 2025-26 or 2026-27 rates.
For the full plain-English guide to every UK tax code letter, prefix and suffix, see UK Tax Codes Explained 2026-27.
Sources
Tax code rules from gov.uk/tax-codes. Income tax rates from HMRC. Effective tax figures computed live from central configuration — correct for 2025-26.