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 2026-27 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.
What you'll actually pay vs the standard code
D1 compared with 1257L — the standard code most single-job employees with no adjustments are on — at the same salary, 2026-27 rates.
| Annual salary | D1 tax | 1257L tax | Difference |
|---|---|---|---|
| £30,000 | £13,500 | £3,486 | +£10,014 |
| £50,000 | £22,500 | £7,486 | +£15,014 |
| £80,000 | £36,000 | £19,432 | +£16,568 |
Should you be on tax code D1?
D1 is usually used if you have more than one job or pension. If you only have one source of income, you would normally expect a code such as 1257L (or the S / C equivalent), so check it with HMRC.
Why you have this code
- A second job or pension for an additional-rate taxpayer, taxed at 45% because your other income already uses the lower bands
- HMRC has been told your main income already exceeds the additional-rate threshold
How to fix it if D1 is wrong
- Check your current code in the HMRC app, your Personal Tax Account, or your latest P2 coding notice or payslip.
- New job with no P45? Ask your employer for a Starter Checklist — completing it correctly is what moves you off a temporary code.
- Not sure what your P45 figures mean, or already overpaid? See the P45 box-by-box guide to decode what your employer reported, or run the tax refund estimator to check what you might be owed.
- If HMRC agrees your code was wrong, most in-year corrections refund automatically through payroll; larger over- or underpayments are settled via a P800 calculation after the tax year ends.
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.
FAQ
What does tax code D1 mean?
How much tax will I pay on tax code D1?
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 2026-27.